A Quantitative Assessment of the Total Inward Leakage of NaCl Aerosol Representing Submicron-Size Bioaerosol Through N95 Filtering Facepiece Respirators and Surgical Masks

Abstract: Respiratory protection provided by a particulate respirator is a function of particle penetration through filter media and through faceseal leakage. Faceseal leakage largely contributes to the penetration of particles through a respirator and compromises protection. When faceseal leaks arise, filter penetration is assumed to be negligible. The contribution of filter penetration and faceseal leakage to total inward leakage (TIL) of submicron-size bioaerosols is not well studied. To address this issue, TIL values for two N95 filtering facepiece respirator (FFR) models and two surgical mask (SM) models sealed to a manikin were measured at 8 L and 40 L breathing minute volumes with different artificial leak sizes. TIL values for different size (20–800 nm, electrical mobility diameter) NaCl particles representing submicron-size bioaerosols were measured using a scanning mobility particle sizer. Efficiency of filtering devices was assessed by measuring the penetration against NaCl aerosol similar to the method used for NIOSH particulate filter certification. Results showed that the most penetrating particle size (MPPS) was ~45 nm for both N95 FFR models and one of the two SM models, and ~350 nm for the other SM model at sealed condition with no leaks as well as with different leak sizes. TIL values increased with increasing leak sizes and breathing minute volumes. Relatively, higher efficiency N95 and SM models showed lower TIL values. Filter efficiency of FFRs and SMs influenced the TIL at different flow rates and leak sizes. Overall, the data indicate that good fitting higher-efficiency FFRs may offer higher protection against submicron-size bioaerosols.


Protecting health care workers from SARS and other respiratory pathogens: A review of the infection control literature

Abstract: BACKGROUND: Severe Acute Respiratory Syndrome (SARS) was responsible for outbreaks in Canada, China, Hong Kong, Vietnam, and Singapore. SARS focused attention on the adequacy of and compliance with infection control practices in preventing airborne and droplet-spread transmission of infectious agents. METHODS: This paper presents a review of the current scientific knowledge with respect to the efficacy of personal protective equipment in preventing the transmission of respiratory infections. The effectiveness of infection control polices and procedures used in clinical practice is examined. RESULTS: Literature searches were conducted in several databases for articles published in the last 15 years that related to infection control practices, occupational health and safety issues, environmental factors, and other issues of importance in protecting workers against respiratory infections in health care settings. CONCLUSION: Failure to implement appropriate barrier precautions is responsible for most nosocomial transmissions. However, the possibility of a gradation of infectious particles generated by aerosolizing procedures suggests that traditional droplet transmission prevention measures may be inadequate in some settings. Further research is needed in this area.


Gastrointestinal endoscopy during COVID-19 pandemic: an updated review of guidelines and statements from international and national societies


Physiologic and other effects and compliance with long-term respirator use among medical intensive care unit nurses

Abstract: BACKGROUND: Long-term use of respiratory protection may be necessary, but compliance may be low, and physiologic effects have not been well evaluated. METHODS: Ten nurses participated; physiologic effects, subjective symptoms, and compliance with wearing an N95 alone or with a surgical mask overlay were assessed. Longitudinal analysis based on multivariate linear regression models assessed changes in outcome variables (CO(2), O(2), heart rate, perceived comfort items, compliance measures, and others). Analyses compared changes over time, and compared wearing only an N95 to wearing an N95 with a surgical mask overlay. RESULTS: Most nurses (90%, n = 9) tolerated wearing respiratory protection for two 12-hour shifts. CO(2) levels increased significantly compared with baseline measures, especially when comparing an N95 with a surgical mask to only an N95, but changes were not clinically relevant. Perceived exertion; perceived shortness of air; and complaints of headache, lightheadedness, and difficulty communicating also increased over time. Almost one-quarter (22%) of respirator removals were due to reported discomfort. N95 adjustments increased over time, but other compliance measures did not vary by time. Compliance increased on day 2, except for adjustments, touching under the N95, and eye touches. CONCLUSION: Long-term use of respiratory protection did not result in any clinically relevant physiologic burden for health care personnel, although many subjective symptoms were reported. N95 compliance was fairly high.


what alcohol sanitizer kills coronavirus

Development of Nano-Antimicrobial Biomaterials for Biomedical Applications

Abstract: Around the globe, there is a great concern about controlling growth of pathogenic microorganisms for the prevention of infectious diseases. Moreover, the greater incidences of cross contamination and overuse of drugs has contributed towards the development of drug resistant microbial strains making conditions even worse. Hospital acquired infections pose one of the leading complications associated with implantation of any biomaterial after surgery and critical care. In this regard, developing non-conventional antimicrobial agents which would prevent the aforementioned causes is under the quest. The rapid development in nanoscience and nanotechnology has shown promising potential for developing novel biocidal agents that would integrate with a biomaterial to prevent bacterial colonization and biofilm formation. Metals with inherent antimicrobial properties such as silver, copper, zinc at nano scale constitute a special class of antimicrobials which have broad spectrum antimicrobial nature and pose minimum toxicity to humans. Hence, novel biomaterials that inhibit microbial growth would be of great significance to eliminate medical device/instruments associated infections. This chapter comprises the state-of-art advancements in the development of nano-antimicrobial biomaterials for biomedical applications. Several strategies have been targeted to satisfy few important concern such as enhanced long term antimicrobial activity and stability, minimize leaching of antimicrobial material and promote reuse. The proposed strategies to develop new hybrid antimicrobial biomaterials would offer a potent antibacterial solution in healthcare sector such as wound healing applications, tissue scaffolds, medical implants, surgical devices and instruments.


Efficient inactivation of SARS-CoV-2 by WHO-recommended hand rub formulations and alcohols

Abstract: The recent emergence of Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causing COVID-19 is a major burden for health care systems worldwide. It is important to address if the current infection control instructions based on active ingredients are sufficient. We therefore determined the virucidal activity of two alcohol-based hand rub solutions for hand disinfection recommended by the World Health Organization (WHO), as well as commercially available alcohols. Efficient SARS-CoV-2 inactivation was demonstrated for all tested alcohol-based disinfectants. These findings show the successful inactivation of SARS-CoV-2 for the first time and provide confidence in its use for the control of COVID-19. Importance The current COVID-19 outbreak puts a huge burden on the world’s health care systems. Without effective therapeutics or vaccines being available, effective hygiene measure are of utmost importance to prevent viral spreading. It is therefore crucial to evaluate current infection control strategies against SARS-CoV-2. We show the inactivation of the novel coronavirus for the first time and endorse the importance of disinfectant-based hand hygiene to reduce SARS-CoV-2 transmission.


Epidemiologic background of hand hygiene and evaluation of the most important agents for scrubs and rubs.

Abstract: The etiology of nosocomial infections, the frequency of contaminated hands with the different nosocomial pathogens, and the role of health care workers' hands during outbreaks suggest that a hand hygiene preparation should at least have activity against bacteria, yeasts, and coated viruses. The importance of efficacy in choosing the right hand hygiene product is reflected in the new Centers for Disease Control and Prevention guideline on hand hygiene (J. M. Boyce and D. Pittet, Morb. Mortal. Wkly. Rep. 51:1-45, 2002). The best antimicrobial efficacy can be achieved with ethanol (60 to 85%), isopropanol (60 to 80%), and n-propanol (60 to 80%). The activity is broad and immediate. Ethanol at high concentrations (e.g., 95%) is the most effective treatment against naked viruses, whereas n-propanol seems to be more effective against the resident bacterial flora. The combination of alcohols may have a synergistic effect. The antimicrobial efficacy of chlorhexidine (2 to 4%) and triclosan (1 to 2%) is both lower and slower. Additionally, both agents have a risk of bacterial resistance, which is higher for chlorhexidine than triclosan. Their activity is often supported by the mechanical removal of pathogens during hand washing. Taking the antimicrobial efficacy and the mechanical removal together, they are still less effective than the alcohols. Plain soap and water has the lowest efficacy of all. In the new Centers for Disease Control and Prevention guideline, promotion of alcohol-based hand rubs containing various emollients instead of irritating soaps and detergents is one strategy to reduce skin damage, dryness, and irritation. Irritant contact dermatitis is highest with preparations containing 4% chlorhexidine gluconate, less frequent with nonantimicrobial soaps and preparations containing lower concentrations of chlorhexidine gluconate, and lowest with well-formulated alcohol-based hand rubs containing emollients and other skin conditioners. Too few published data from comparative trials are available to reliably rank triclosan. Personnel should be reminded that it is neither necessary nor recommended to routinely wash hands after each application of an alcohol-based hand rub. Long-lasting improvement of compliance with hand hygiene protocols can be successful if an effective and accessible alcohol-based hand rub with a proven dermal tolerance and an excellent user acceptability is supplied, accompanied by education of health care workers and promotion of the use of the product.


Outbreaks where food workers have been implicated in the spread of foodborne disease. Part 10. Alcohol-based antiseptics for hand disinfection and a comparison of their effectiveness with soaps.

Abstract: Alcohol compounds are increasingly used as a substitute for hand washing in health care environments and some public places because these compounds are easy to use and do not require water or hand drying materials. However, the effectiveness of these compounds depends on how much soil (bioburden) is present on the hands. Workers in health care environments and other public places must wash their hands before using antiseptics and/or wearing gloves. However, alcohol-based antiseptics, also called rubs and sanitizers, can be very effective for rapidly destroying some pathogens by the action of the aqueous alcohol solution without the need for water or drying with towels. Alcohol-based compounds seem to be the most effective treatment against gram-negative bacteria on lightly soiled hands, but antimicrobial soaps are as good or better when hands are more heavily contaminated. Instant sanitizers have no residual effect, unlike some antimicrobial soaps that retain antimicrobial activity after the hygienic action has been completed, e.g., after hand washing. Many alcohol-based hand rubs have antimicrobial agents added to them, but each formulation must be evaluated against the target pathogens in the environment of concern before being considered for use. Wipes also are widely used for quick cleanups of hands, other body parts, and surfaces. These wipes often contain alcohol and/or antimicrobial compounds and are used for personal hygiene where water is limited. However, antiseptics and wipes are not panaceas for every situation and are less effective in the presence of more than a light soil load and against most enteric viruses.


Hand sanitisers amid CoViD-19: A critical review of alcohol-based products on the market and formulation approaches to respond to increasing demand

Abstract: The world is facing a medical crisis amid the CoViD-19 pandemic and the role of adequate hygiene and hand sanitisers is inevitable in controlling the spread of infection in public places and healthcare institutions. There has been a great surge in demand for hand sanitisation products leading to shortages in their supply. A consequent increase of substandard products in the market has raised safety concerns. This article, therefore, presents a critical review of hand sanitation approaches and products available on the market in light of the scientific evidence available to date. This review also provides a range of hand sanitisation product formulations, and manufacturing instructions to allow for extemporaneous preparations at the community and hospital pharmacies during this urgent crisis. In addition, this emergent situation is expected to continue, hence hand sanitisers will be in demand for an extended time, and the availability and purchase of substandard products on the market create an ongoing safety concern. Therefore, this article shall also provide various commercial organisations, interested in stepping forward the production and marketing of hand sanitisers, with a guide on the development of products of standardised ingredients and formulations.


Hand Sanitizers: A Review on Formulation Aspects, Adverse Effects, and Regulations

Abstract: Hand hygiene is of utmost importance as it may be contaminated easily from direct contact with airborne microorganism droplets from coughs and sneezes. Particularly in situations like pandemic outbreak, it is crucial to interrupt the transmission chain of the virus by the practice of proper hand sanitization. It can be achieved with contact isolation and strict infection control tool like maintaining good hand hygiene in hospital settings and in public. The success of the hand sanitization solely depends on the use of effective hand disinfecting agents formulated in various types and forms such as antimicrobial soaps, water-based or alcohol-based hand sanitizer, with the latter being widely used in hospital settings. To date, most of the effective hand sanitizer products are alcohol-based formulations containing 62%-95% of alcohol as it can denature the proteins of microbes and the ability to inactivate viruses. This systematic review correlated with the data available in Pubmed, and it will investigate the range of available hand sanitizers and their effectiveness as well as the formulation aspects, adverse effects, and recommendations to enhance the formulation efficiency and safety. Further, this article highlights the efficacy of alcohol-based hand sanitizer against the coronavirus.


Inactivation of Severe Acute Respiratory Syndrome Coronavirus 2 by WHO-Recommended Hand Rub Formulations and Alcohols

Abstract: Infection control instructions call for use of alcohol-based hand rub solutions to inactivate severe acute respiratory syndrome coronavirus 2. We determined the virucidal activity of World Health Organization-recommended hand rub formulations, at full strength and multiple dilutions, and of the active ingredients. All disinfectants demonstrated efficient virus inactivation.


Hand disinfection in the combat against Covid-19

Abstract: The World Health Organization (WHO) has declared a global health emergency over a new coronavirus. The new corona virus (SARS-CoV-2) has raised global attention with raising concerns of rapid spread from human-to-human. Like severe acute respiratory syndrome (SARS)-nCoV, 2019-nCoV can be passed directly from person to person by respiratory droplets, and may also be transmitted through contact and fomites.


Evaluation of World Health Organization-Recommended Hand Hygiene Formulations

Abstract: As a result of the coronavirus disease pandemic, commercial hand hygiene products have become scarce and World Health Organization (WHO) alcohol-based hand rub formulations containing ethanol or isopropanol are being produced for hospitals worldwide. Neither WHO formulation meets European Norm 12791, the basis for approval as a surgical hand preparation, nor satisfies European Norm 1500, the basis for approval as a hygienic hand rub. We evaluated the efficacy of modified formulations with alcohol concentrations in mass instead of volume percentage and glycerol concentrations of 0.5% instead of 1.45%. Both modified formulations met standard requirements for a 3-minute surgical hand preparation, the usual duration of surgical hand treatment in most hospitals in Europe. Contrary to the originally proposed WHO hand rub formulations, both modified formulations are appropriate for surgical hand preparation after 3 minutes when alcohol concentrations of 80% wt/wt ethanol or 75% wt/wt isopropanol along with reduced glycerol concentration (0.5%) are used.


Hidden threat lurking behind the alcohol sanitizers in COVID-19 outbreak

Abstract: The ongoing COVID-19 pandemic has made various challenges for communications all over the world. Nowadays hand hygiene practices with alcohol sanitizers are an unavoidable reality for many people, which cause skin dryness and flaking. The current short communication has been explained about monitoring the quality control of alcohol concentrations and hand rub formulation, which needs more attention and should consider meticulous in this crisis.


The pandemic of COVID-19 and its implications for the purity and authenticity of alcohol-based hand sanitizers: The health risks associated with falsified sanitizers and recommendations for regulatory and public health bodies

Abstract: With the beginning of the pandemic of COVID-19 throughout the world, the demand and consumption of hand sanitizers has increased, which had led to a sharp crunch in these products at all levels. This shortage has led to an increase in the prevalence of falsified alcohol-based hand sanitizers, including the illegal addition of methanol to hand sanitizers and the production of hand sanitizers with an alcohol concentration of less than 60%. These findings indicate that regulatory and public health bodies should take an active role in ensuring the safety and quality of antimicrobial products such as alcohol-based hand sanitizers at every stage of the products' lifecycle, including distribution, manufacture and import.


Hand Sanitizers: A Review of Ingredients, Mechanisms of Action, Modes of Delivery, and Efficacy Against Coronaviruses

Abstract: BACKGROUND: The emergence of the novel virus, SARS-CoV-2, has posed unprecedented challenges to public health around the world. Currently, strategies to deal with COVID-19 are purely supportive and preventative, aimed at reducing transmission. An effective and simple method for reducing transmission of infections in the public or healthcare settings is hand hygiene. Unfortunately, little is known regarding the efficacy of hand sanitizers against SARS-CoV-2. METHODS: In this review, an extensive literature search was performed to succinctly summarize the primary active ingredients and mechanisms of action of hand sanitizers, compare the effectiveness and compliance of gel and foam sanitizers, and predict whether alcohol and non-alcohol hand sanitizers would be effective against SARS-CoV-2. RESULTS: Most alcohol based hand sanitizers are effective at inactivating enveloped viruses, including coronaviruses. With what is currently known in the literature, one may not confidently suggest one mode of hand sanitizing delivery over the other. When hand washing with soap and water is unavailable, a sufficient volume of sanitizer is necessary to ensure complete hand coverage, and compliance is critical for appropriate hand hygiene. CONCLUSIONS: By extrapolating effectiveness of hand sanitizers on viruses of similar structure to SARS-CoV-2, this virus should be effectively inactivated with current hand hygiene products, though future research should attempt to determine this directly.


Comparison of national and subnational guidelines for hand hygiene

Abstract: Summary Hand hygiene promotion is considered as the cornerstone for healthcare-associated infection prevention. Over the past years, hand hygiene guidelines have been developed by different agencies at international, national and subnational levels. A comparison of these documents could help in understanding recommendations in different parts of the world and the methods used for their development. Guidelines were identified through search engines, electronic libraries, and personal contacts, and their content was analysed using an adapted version of a tool from the European DG XII-funded HARMONY project. Twenty-two guidelines were retrieved and 21 were evaluated. Documents varied in scope, approach, content and terminology. Some were primarily advisory directives, whereas others focused on the technical issues of why, when, and how to perform hand hygiene. The extent to which evidence was collected and assessed varied considerably and details were provided only in very few. Grading systems and definitions to indicate the strength of evidence and recommendations also differed. The intended outcome was to improve hand hygiene practices in healthcare, thus leading to a reduction of healthcare-associated infections and/or antimicrobial resistance. Although overall agreement on indications and procedures was noted, the range and depth of recommendations on best practices and implementation varied. Essential aspects such as compliance measurement and audits to assess guideline effectiveness were neglected in most documents. In conclusion, there is a need for a more consistent approach leading to recommendations based on a thorough evaluation of evidence and applicable worldwide. Aspects related to implementation and impact monitoring deserve greater attention.


Predictors of hand hygiene practice among Saudi nursing students: A cross-sectional self-reported study

Abstract: Summary Hand hygiene is an important component of infection control, which is critical to ensuring patients’ safety in hospitals. Nursing students are regarded as healthcare workers in training and can also be vehicles of cross-contamination within the hospital. Thus, this study aimed to identify the predictors of hand hygiene practice among Saudi nursing students. A descriptive, cross-sectional, self-reported study was conducted among 198 Saudi nursing students. Knowledge, attitude, and practice of hand hygiene were assessed using the WHO Hand Hygiene Knowledge Questionnaire for Health-Care Workers and its adopted scales. A regression analysis was performed to identify the predictors of hand hygiene practice. The respondents demonstrated moderate knowledge of hand hygiene (mean 13.20±2.80). The majority displayed a moderate attitude toward hand hygiene (52.1%), while only a few reported a poor attitude (13.1%). Approximately 68.7%, 29.8%, and 1.5% of the respondents reported moderate, good, and poor practice of hand hygiene, respectively. Having a good attitude toward hand hygiene, being male, being aware that hand hygiene is an effective intervention in preventing healthcare-associated infections (HAIs), attendance at hand hygiene trainings and seminars, and being in the lower academic level of nursing education were identified as predictors of better hand hygiene practice. The importance of ensuring a positive attitude toward hand hygiene and improving awareness of hand hygiene is emphasized, as are educational interventions. Educational interventions should be implemented to reinforce knowledge and instill a positive attitude toward hand hygiene.


Handwashing and risk of respiratory infections: a quantitative systematic review

Abstract: Objective To determine the effect of handwashing on the risk of respiratory infection. Methods We searched PubMed, CAB Abstracts, Embase, Web of Science, and the Cochrane library for articles published before June 2004 in all languages. We had searched reference lists of all primary and review articles. Studies were included in the review if they reported the impact of an intervention to promote hand cleansing on respiratory infections. Studies relating to hospital‐acquired infections, long‐term care facilities, immuno‐compromised and elderly people were excluded. We independently evaluated all studies, and inclusion decisions were reached by consensus. From a primary list of 410 articles, eight interventional studies met the eligibility criteria. Results All eight eligible studies reported that handwashing lowered risks of respiratory infection, with risk reductions ranging from 6% to 44% [pooled value 24% (95% CI 6–40%)]. Pooling the results of only the seven homogenous studies gave a relative risk of 1.19 (95% CI 1.12%–1.26%), implying that hand cleansing can cut the risk of respiratory infection by 16% (95% CI 11–21%). Conclusions Handwashing is associated with lowered respiratory infection. However, studies were of poor quality, none related to developing countries, and only one to severe disease. Rigorous trials of the impact of handwashing on acute respiratory tract infection morbidity and mortality are urgently needed, especially in developing countries.


Zinc pyrithione in alcohol-based products for skin antisepsis: Persistence of antimicrobial effects

Abstract: Alcohol-based products for skin antisepsis have a long history of safety and efficacy in the United States and abroad. However, alcohol alone lacks the required antimicrobial persistence to provide for the sustained periods of skin antisepsis desired in the clinical environment. Therefore, alcohol-based products must have a preservative agent such as iodine/iodophor compounds, chlorhexidine gluconate, or zinc pyrithione, to extend its antimicrobial effects. Iodine, iodophors, and chlorhexidine gluconate are well-characterized antimicrobials and preservatives. The thrust of our effort was to examine the characteristics of the lesser-known zinc pyrithione and to evaluate its utility as a preservative in the formulation of alcohol-based products for skin antisepsis. This work includes a literature review of current zinc pyrithione applications in drugs and cosmetics, a safety and toxicity evaluation, consideration of the proposed mechanisms of antimicrobial action, in vitro and in vivo efficacy data, and a discussion of the mechanisms that confer the desired antimicrobial persistence. In addition, alcohol-based, zinc pyrithione-preserved, commercially available products of skin antisepsis are compared with other commercially available antimicrobials used for skin antisepsis and with additional alcohol-based products with different preservatives. The authors' conclusion is that zinc pyrithione is not only a safe and effective antimicrobial but that its use in certain alcohol-based formulations results in antimicrobial efficacy exceeding that of iodine and chlorhexidine gluconate.


Introduction to Food Irradiation and Medical Sterilization

Abstract: This chapter is comprehensive overview of sterilization and disinfectant processes used for food-borne disease control and medical sterilization. Pathogens such as bacteria, viruses, and endospores are described along with other infectious agents. The processes for controlling these infectious agents in food are summarized. These processes include not only irradiation by the two most important processes, electron beam and gamma ray, but by other processes such as ultraviolet, microwave, and infrared radiation. Medical sterilization and disinfectant processes are reviewed. Besides irradiative processes, thermal processes such as steam autoclave and dry heat are reviewed. Many liquid and gaseous chemical disinfectants are covered. The commercially important ethylene oxide sterilization process is discussed. Dealing with bioterrorism agents is briefly discussed. Throughout this chapter, the mechanisms, the irradiation, sterilization, and chemical disinfectant processes used to destroy the pathogens are discussed often in chemical detail.


Methanol Poisoning Emerging as the Result of COVID-19 Outbreak; Radiologic Perspective


A unique water optional health care personnel handwash provides antimicrobial persistence and residual effects while decreasing the need for additional products

Abstract: BACKGROUND: The Centers for Disease Control and Prevention (CDC) has published guidelines for hand hygiene practices, recommending a handwash regimen that alternates between waterless alcohol products and antimicrobial or nonantimicrobial soap and water. The advent of an alcohol-based product that can be used with or without water (ie, water optional) to decontaminate the hands while providing immediacy of kill and antimicrobial persistence could reduce the confusion associated with handwash guidelines. Such a product has been developed, is alcohol-based (61%), and zinc pyrithione (ZPT) preserved (61% alcohol-ZPT) and has proven to be fully compliant with the Food and Drug Administration (FDA) and CDC guidelines. METHODS: FDA-required testing of the 61% alcohol-ZPT product for the health care personnel handwash indication was performed as outlined in the Tentative Final Monograph (TFM) for Health-Care Antiseptic Drug Products, employing waterless and water-aided product applications. It was next assessed for antimicrobial persistence and residual effects by comparing it, in separate waterless and water-aided applications, with commonly available handwashes containing various antimicrobials in a 5-day study employing 49 subjects, in which samples were collected immediately and at 4 hours and 8 hours postapplication. The skin conditioning properties of this formulation were investigated via appropriate methods. RESULTS: The 61% alcohol-ZPT product easily produced >3.0 log(10) reduction in the indicator strain (Serratia marcescens) following the first wash, exceeding the 2.0 log(10) FDA requirement. This level of performance was maintained through the tenth wash, surpassing the 3.0 log(10) FDA requirement for the handwash indication. For the assessment of persistence and residual effect in the waterless mode, the water-optional, 61% alcohol-ZPT product consistently produced log(10) reductions of nearly 3.5 or greater at every point over the entire study period. In the water-aided configuration, similar results were obtained as log(10) reductions of 2.5 were observed. The formulation is nonirritating, actually contributing to hand skin condition. CONCLUSIONS: The 61% alcohol-ZPT product exceeds all FDA criteria for the health care personnel handwash indication and is a significant advancement in the concept of skin antisepsis. It represents a single product suitable for use in all hand hygiene settings, demonstrating improved antimicrobial persistence and residual effects. The 61% alcohol-ZPT formulation contributes positively to overall hand conditioning, and a previously reported study has documented it to be virucidal for several DNA and RNA viruses.


Disinfection and Sterilization in Health Care Facilities An Overview and Current Issues

Abstract: When properly used, disinfection and sterilization can ensure the safe use of invasive and noninvasive medical devices. The method of disinfection and sterilization depends on the intended use of the medical device: critical items (contact sterile tissue) must be sterilized before use; semicritical items (contact mucous membranes or nonintact skin) must be high-level disinfected; and noncritical items (contact intact skin) should receive low-level disinfection. Cleaning should always precede high-level disinfection and sterilization. Current disinfection and sterilization guidelines must be strictly followed.


Personal Protective Equipment Recommendations Based on COVID-19 Route of Transmission


Hidden threat lurking behind the alcohol sanitizers in COVID‐19 outbreak

Abstract: The ongoing COVID‐19 pandemic has made various challenges for communications all over the world. Nowadays hand hygiene practices with alcohol sanitizers are an unavoidable reality for many people, which cause skin dryness and flaking. The current short communication has been explained about monitoring the quality control of alcohol concentrations and hand rub formulation, which needs more attention and should consider meticulous in this crisis.


Are your hands clean enough for point-of-care electrolyte analysis?

Abstract: Summary Aim To investigate clinically significant analytical interference in point-of-care electrolyte analysis caused by contamination of blood specimens with hand disinfectant. Methods Six different hand hygiene products were added separately to heparinised blood samples in varying amounts as contaminant. The contaminated samples were analysed by three different blood gas and electrolyte analysers for assessing interference on measured whole blood sodium and potassium concentrations. Results There were significant analytical interferences caused by hand hygiene product contamination that varied depending on the combination of disinfectant and analyser. Small amounts of Microshield Antibacterial Hand Gel contamination caused large increases in measured sodium concentration. Such effect was much greater compared with the other five products tested, and started to occur at much lower levels of contamination. There was a trend towards lower sodium results in blood samples contaminated with Hexol Antiseptic Lotion (Hexol), the hand hygiene product that we used initially. Apart from AiE Hand Sanitizer, all the other hand disinfectants, especially Hexol, significantly elevated the measured potassium concentration, particularly when a direct ion-selective electrode method was used for measurement. Conclusion Hand disinfectant products can significantly interfere with blood electrolyte analysis. Proper precautions must be taken against contamination since the resultant errors can adversely affect the clinical management of patients.


Religion and culture: Potential undercurrents influencing hand hygiene promotion in health care

Abstract: BACKGROUND: Health care–associated infections affect hundreds of millions of patients worldwide each year. The World Health Organization's (WHO) First Global Patient Safety Challenge, “Clean Care is Safer Care,” is tackling this major patient safety problem, with the promotion of hand hygiene in health care as the project's cornerstone. WHO Guidelines on Hand Hygiene in Healthcare have been prepared by a large group of international experts and are currently in a pilot-test phase to assess feasibility and acceptability in different health care settings worldwide. METHODS: An extensive literature search was conducted and experts and religious authorities were consulted to investigate religiocultural factors that may potentially influence hand hygiene promotion, offer possible solutions, and suggest areas for future research. RESULTS: Religious faith and culture can strongly influence hand hygiene behavior in health care workers and potentially affect compliance with best practices. Interesting data were retrieved on specific indications for hand cleansing according to the 7 main religions worldwide, interpretation of hand gestures, the concept of “visibly dirty” hands, and the use of alcohol-based hand rubs and prohibition of alcohol use by some religions. CONCLUSIONS: The impact of religious faith and cultural specificities must be taken into consideration when implementing a multimodal strategy to promote hand hygiene on a global scale.


Surfactants as Antimicrobials: A Brief Overview of Microbial Interfacial Chemistry and Surfactant Antimicrobial Activity

Abstract: In this brief overview of a large and complex subject, as presented at the 2018 Surfactants in Solution conference, the need for, and impact of, hard surface antimicrobial products is demonstrated. The composition of the interfaces of three common classes of pathological microbes, bacteria, viruses, and fungi, is discussed so that surfactant and cleaning product development scientists better understand their interfacial characteristics. Studies of antimicrobial efficacy from the four major classes of surfactants (cationic, anionic, amphoteric, and nonionic) are shown. The need for preservatives in surfactants is elucidated. The regulatory aspects of antimicrobials in cleaning products to make antimicrobial claims are stressed.


Low-cost production of handrubs and face shields in developing countries fighting the COVID19 pandemic


Development and virucidal activity of a novel alcohol-based hand disinfectant supplemented with urea and citric acid

Abstract: BACKGROUND: Hand disinfectants are important for the prevention of virus transmission in the health care system and environment. The development of broad antiviral spectrum hand disinfectants with activity against enveloped and non-enveloped viruses is limited due to a small number of permissible active ingredients able to inactivate viruses. METHODS: A new hand disinfectant was developed based upon 69.39 % w/w ethanol and 3.69 % w/w 2-propanol. Different amounts of citric acid and urea were added in order to create a virucidal claim against poliovirus (PV), adenovirus type 5 (AdV) and polyomavirus SV40 (SV40) as non-enveloped test viruses in the presence of fetal calf serum (FCS) as soil load. The exposure time was fixed to 60 s. RESULTS: With the addition of 2.0 % citric acid and 2.0 % urea an activity against the three test viruses was achieved demonstrating a four log(10) reduction of viral titers. Furthermore, this formulation was able to inactivate PV, AdV, SV40 and murine norovirus (MNV) in quantitative suspension assays according to German and European Guidelines within 60 s creating a virucidal claim. For inactivation of vaccinia virus and bovine viral diarrhea virus 15 s exposure time were needed to demonstrate a 4 log(10) reduction resulting in a claim against enveloped viruses. Additionally, it is the first hand disinfectant passing a carrier test with AdV and MNV. CONCLUSIONS: In conclusion, this new formulation with a low alcohol content, citric acid and urea is capable of inactivating all enveloped and non-enveloped viruses as indicated in current guidelines and thereby contributing as valuable addition to the hand disinfection portfolio.


Back to basics: hand hygiene and isolation

Abstract: PURPOSE OF REVIEW: Hand hygiene and isolation are basic, but very effective, means of preventing the spread of pathogens in healthcare. Although the principle may be straightforward, this review highlights some of the controversies regarding the implementation and efficacy of these interventions. RECENT FINDINGS: Hand hygiene compliance is an accepted measure of quality and safety in many countries. The evidence for the efficacy of hand hygiene in directly reducing rates of hospital-acquired infections has strengthened in recent years, particularly in terms of reduced rates of staphylococcal sepsis. Defining the key components of effective implementation strategies and the ideal method(s) of assessing hand hygiene compliance are dependent on a range of factors associated with the healthcare system. Although patient isolation continues to be an important strategy, particularly in outbreaks, it also has some limitations and can be associated with negative effects. Recent detailed molecular epidemiology studies of key healthcare-acquired pathogens have questioned the true efficacy of isolation, alone as an effective method for the routine prevention of disease transmission. SUMMARY: Hand hygiene and isolation are key components of basic infection control. Recent insights into the benefits, limitations and even adverse effects of these interventions are important for their optimal implementation.


Bactericidal and Virucidal Activity of Povidone-Iodine and Chlorhexidine Gluconate Cleansers in an In Vivo Hand Hygiene Clinical Simulation Study

Abstract: INTRODUCTION: Standard in vitro and in vivo tests help demonstrate efficacy of hand hygiene products; however, there is no standard in vivo test method for viruses. We investigated the bactericidal and virucidal efficacy of povidone-iodine (PVP-I) 7.5% scalp and skin cleanser, chlorhexidine gluconate (CHG) 4% hand cleanser and the reference hand wash (soft soap) in 15 healthy volunteers following European Standard EN1499 (hygienic hand wash test method for bacteria), which was adapted for virucidal testing. METHODS: Separate test series were performed for bactericidal (Escherichia coli) and virucidal [murine norovirus (MNV)] testing. After pre-washing and artificial contamination of hands with test organisms, volunteers underwent testing with 3 and 5 mL of each product for contact times of 15, 30 and 60 s according to a Latin-square randomization. The number of test organisms released from fingertips into sampling fluids was assessed before and after hand washing and mean log(10) reduction factor (RF) was calculated. RFs (test-reference) were compared using a Wilcoxon–Wilcox multiple comparisons test per EN1499; efficacy was concluded if p ≤ 0.01. RESULTS: PVP-I 7.5% and CHG 4% cleansers both passed EN1499 requirements against E. coli, with statistically significantly greater (p ≤ 0.01) mean log(10) RFs compared with reference soft soap across all tests (PVP-I: 4.09–5.27; CHG: 4.12–5.22; soap: 2.75–3.11). The experimental design using EN1499 was applicable to testing with MNV as discriminatory and reproducible results were generated. Mean log(10) RFs of MNV were statistically significantly greater for PVP-I (1.57–2.57) compared with soft soap (1.24–1.62), while mean log(10) RFs with CHG (0.90–1.34) were lower than for soft soap across all tests. CONCLUSION: PVP-I 7.5% cleanser showed superior efficacy against MNV compared to soft soap and CHG 4% cleanser, while both PVP-I and CHG were superior to soft soap against E. coli. The experimental set-up may be applicable to future testing for antiviral hand washes. FUNDING: Mundipharma Manufacturing Pte Ltd. PLAIN LANGUAGE SUMMARY: Plain language summary available for this article.


Infectious Disease Management and Control with Povidone Iodine

Abstract: With reports of vancomycin-resistant enterococci recently emerging in hospital settings, renewed focus is turning to the importance of multifaceted infection prevention efforts. Careful compliance with established hygiene practices by healthcare workers together with effective antiseptic options is essential for the protection of patients from infectious agents. For over 60 years, povidone iodine (PVP-I) formulations have been shown to limit the impact and spread of infectious diseases with potent antiviral, antibacterial and antifungal effects. In addition to a lack of reported resistance, the benefits of PVP-I include an excellent safety profile and a broad spectrum of effect due to its multimodal action. Studies have shown that hand washing with PVP-I-based antiseptics is effective for the decontamination of skin, while PVP-I mouthwashes and gargles significantly reduce viral load in the oral cavity and the oropharynx. The importance of PVP-I has been emphasised by its inclusion in the World Health Organization’s list of essential medicines, and high potency for virucidal activity has been observed against viruses of significant global concern, including hepatitis A and influenza, as well as the Middle-East Respiratory Syndrome and Sudden Acute Respiratory Syndrome coronaviruses. Together with its diverse applications in antimicrobial control, broad accessibility across the globe, and outstanding safety and tolerability profile, PVP-I offers an affordable, potent, and widely available antiseptic option. Funding Mundipharma Singapore Holding Pte Limited.


Effects of hand disinfection with alcohol hand rub, ozonized water, or soap and water: time for reconsideration?

Abstract: The effect of alcohol hand rub was tested in eradicating Escherichia coli, and compared with hand wash using ozonized tap water or soap and water. Alcohol eradicated all bacteria in 10 out of 35 participants, but with an average (SD) of 2330 (4227) cfu/mL left after disinfection, whereas ozonized water removed all bacteria in 10 out of 55 participants, with an average of only 538 (801) cfu/mL left (P = 0.045). Soap washing was the most effective with total removal of bacteria in six out of 20 participants, with an average of 98 (139) cfu/mL (P = 0.048 and 0.018 versus ozonized water and alcohol, respectively).


Rate of Compliance with Hand Hygiene by Dental Healthcare Personnel (DHCP) within a Dentistry Healthcare First Aid Facility

Abstract: OBJECTIVES: To evaluate the compliance with the opportunities of hand hygiene by dentistry school healthcare professionals, as well as the higher choice products. METHODS: Through direct observation, the oral healthcare team-professors, oral and maxillofacial surgery residents, graduation students-for daily care were monitored: before performing the first treatment of the shift, after snacks and meals, and after going to the bathroom (initial opportunities) as well as between patients’ care, and after ending the shift (following opportunities). RESULTS: The professors’ category profited 78.4% of all opportunities while residents and graduation students did not reach 50.0% of compliance. Statistically significant data (P≤.05) were seen between categories: professors and residents, professors and graduation students, and between genders within the residents’ category. When opportunities were profited, the preferred choice for hand hygiene was water and soap (82.2%), followed by 70% alcohol (10.2%), and both (7.6%). CONCLUSIONS: Although gloves were worn in all procedures, we concluded that the hygiene compliance by these professionals was under the expectation.


Role of the Renin-Angiotensin System in ARDS

Abstract: The renin-angiotensin system (RAS) is a powerful biological system that plays an important role in regulation of systemic blood pressure through the maintenance of fluid and salt homeostasis. It is a multifactorial system since it includes different components (Fig. 1): The first, renin, was discovered in 1898 [1], whereas the discovery of the last component, angiotensin-converting enzyme 2 (ACE 2), is relatively recent, from 2000 [2, 3]. Three kinds of RAS are known: A) circulating, B) local, and C) intracellular.


EMA: continue use of ACE inhibitors, sartans during COVID-19 pandemic


Inhibitors of the renin-angiotensin system: The potential role in the pathogenesis of COVID-19.

Abstract: Coronavirus disease 2019 (COVID-19), which initially began in China, has spread to other countries of Asia, Europe, America, Africa and Oceania, with the number of confirmed cases and suspected cases increasing each day. According to recently published research, it was found that the majority of the severe cases were elderly, and many of them had at least one chronic disease, especially cardiovascular diseases. Angiotensin-converting enzyme inhibitors/angiotensin receptor blockers (ACEIs/ARBs) are the most widely used drugs for cardiovascular diseases. The clinical effect of ACEIs/ARBs on patients with COVID-19 is still uncertain. This paper describes their potential role in the pathogenesis of COVID-19, which may provide useful in the advice of cardiologists and physicians.


Angiotensin-converting enzyme 2: cardioprotective player in the renin-angiotensin system?


[Role of age, comorbidity and renin- angiotensin-aldosterone system in COVID-19. Effects of ACE inhibitors and angiotensin receptor blockers].

Abstract: The review addressed the relationship of coronavirus disease 2019 (COVID-19) with functioning of the renin-angiotensin-aldosterone axis and the causes for unfavorable prognosis depending on patients' age and comorbidities. The authors discussed in detail potential effects of angiotensin-converting enzyme inhibitors and angiotensin II type 1 receptor antagonists on the risk of infection and the course of COVID-2019 as well as the effect of SARS-COV2 virus on the cardiovascular system.


COVID-19 and cardiovascular diseases: viewpoint for older patients.

Abstract: The coronavirus disease-2019 (COVID-19) is an infectious disease caused by severe acute respiratory syndrome coronavirus 2. The link between cardiovascular disease and COVID-19 appears to be twofold. First, some reports of data indicate that certain groups of patients are more at risk of COVID-19. This includes patients with cardiovascular risk factors or pre-existing cardiovascular conditions and older patients. In addition, these patients incur disproportionately worse outcome. Second, SARS-CoV2 infection can be complicated by life-threatening cardiovascular acute diseases. Despite the rapid evolution of data on this pandemic, this review aims to highlight the cardiovascular considerations related to COVID-19 whether as comorbidities including concerns and uncertainty regarding the effect of renin-angiotensin-aldosterone system (RAAS) inhibitors on angiotensin conversion enzyme 2 or related to acute cardiovascular complications.


Relationship between ACE-inhibitors, ARBs and SARS-CoV-2 infection: where are we?

Abstract: SARS-CoV-2 is spreading rapidly all over the world. The case fatality rate seems higher in cardiovascular disease and hypertension. Other comorbidities do not seem to confer the same risk, therefore the understanding of the relationship between infection and cardiovascular system could be a crucial point for the fight against the virus. A great interest is currently directed towards the angiotensin 2 converting enzyme (ACE 2) which is the SARS-CoV-2 receptor and creates important connections between the virus replication pathway, the cardiovascular system and blood pressure. All cardiovascular conditions share an imbalance of the renin angiotensin system (RAAS) in which ACE 2 plays a central role. In the last few days, much confusion has appeared about the management of therapy with angiotensin converting enzyme inhibitors (ACE-i) and angiotensin receptor blockers (ARBs) in infected patients and in those at risk of critical illness in case of infection. In this article we will try to reorder the major opinions currently emerging on this topic.


[2019 Novel coronavirus, renin-angiotension system imbalance and coronavirus disease 2019].

Abstract: 2019 Novel coronavirus (2019-nCoV) destroys angiotensin converting enzyme 2 (ACE2) and breaks the balance of renin-angiotension system (RAS) by interacting with ACE2. The imbalance of RAS takes part in the development of organ injury of different systems through pro-inflammation, oxidative stress, cell proliferation and so on. 2019-nCoV not only attacks the lung, but also influences many other systems. It is speculated that RAS imbalance plays an important role in the development of multi-organ dysfunction caused by 2019-nCoV, and the usage of angiotensin converting enzyme inhibitor/angiotensin II receptor blocker (ACEI/ARB) may become a new treatment of 2019-nCoV-related organ injury. Further studies are need to confirm the relationship between coronavirus infection, multi-organ injury and RAS imbalance.


The Effect of Coronavirus Disease 2019 on Cardiovascular Diseases.

Abstract: Coronavirus disease 2019 (COVID-19) is a global pandemic affecting the world, seen in more than 1,300,000 patients. COVID-19 acts through the angiotensin-converting enzyme 2 (ACE2) receptor. Cardiovascular comorbidities are more common with COVID-19, and nearly 10% of cases develop myocarditis (22% of critical patients). Further research is needed to continue or discontinue ACE inhibitors and angiotensin receptor blockers, which are essential in hypertension and heart failure in COVID-19. Intensive research is promising for the treatment and prevention of COVID-19.


Comparative impacts of angiotensin converting enzyme inhibitors versus angiotensin II receptor blockers on the risk of COVID-19 mortality.

Abstract: N/A.


Angiotensin converting enzyme 2 (ACE2) and COVID-19: using antihypertensive medications, pharmacogenetic considerations.

Abstract: COVID-19 utilizes the angiotensin-converting enzyme-2 (ACE2) pathway as a means of infection. Early data on COVID-19 suggest heterogeneity in the severity of symptoms during transmission and infection ranging from no symptoms to death. The source of this heterogeneity is likely multifaceted and may have a genetic component. Demographic and clinical comorbidities associated with the severity of infection suggest that possible variants known to influence the renin-angiotensin-aldosterone system pathway (particularly those that influence ACE2) may contribute to the heterogenous infection response. ACE2 and angiotensin(1-7) (the product of ACE2) seem to have a protective effect on the pulmonary and cardiac systems. Hypertension medication modulation, may alter ACE2 and angiotensin(1-7), particularly in variants that have been shown to influence renin-angiotensin-aldosterone system function, which could be clinically useful in patients with COVID-19.


Blocking angiotensin earlier with RAS blockers, statins, and heparin in high-risk COVID-19 patients: Is the remedy here?


Therapy with agents acting on the renin-angiotensin system and risk of SARS-CoV-2 infection.

Abstract: Exposure to agents acting on the renin-angiotensin system was not associated to a risk increase of COVID-19 infection in two Italian matched case-control studies, one nested in hypertensive patients and the other in patients with cardiovascular diseases or diabetes.


A hypothesis for pathobiology and treatment of COVID-19: the centrality of ACE1/ACE2 imbalance.

Abstract: Angiotensin converting enzyme-2 (ACE2) is the receptor for the coronavirus SARS-CoV-2, which causes COVID-19. We propose the following hypothesis: Imbalance in the action of ACE1- and ACE2-derived peptides, thereby enhancing Angiotensin-II (ANG II) signaling, a primary driver of COVID-19 pathobiology. ACE1/ACE2 imbalance occurs due to the binding of SARS-CoV-2 to ACE2, reducing ACE2-mediated conversion of ANG II to ANG peptides that counteract pathophysiological effects of ACE1-generated ANGII. This hypothesis suggests several approaches to treat COVID-19 by restoring ACE1/ACE2 balance: 1) ANG II receptor blockers (ARBs); 2) ACE1 inhibitors (ACEIs); 3) Agonists of receptors activated by ACE2-derived peptides [e.g., ANG (1-7), which activates MAS1]; 4) Recombinant human ACE2 or ACE2 peptides as decoys for the virus. Reducing ACE1/ACE2 imbalance is predicted to blunt COVID-19-associated morbidity and mortality, especially in vulnerable patients. Importantly, approved ARBs and ACEIs can be rapidly repurposed to test their efficacy in treating COVID-19.


Angiotensin-converting enzyme inhibitors, angiotensin II type 1 receptor blockers and risk of COVID 19: information from Bartter's and Gitelman's syndromes patients.


The renin-angiotensin system - a therapeutic target in COVID-19?

Abstract: COVID-19, caused by infection with SARS-CoV-2, is a disease characterised by cough, fever and fatigue, which progresses to life-threatening lung injury in approximately 5% of patients. The SARS-CoV-2 virus enters the cell via ACE2. ACE2 is a component of the renin-angiotensin system (RAS) which has an important counterregulatory effect on the classical ACE-dependent pathway. Several antihypertensives increase ACE2 expression or activity, leading to concern that this may facilitate SARS-CoV-2 entry and worsen COVID-19 disease. However, ACE2 is protective against lung injury while ANG II (which is catabolised by ACE2) is associated with lung injury both in mice and humans. We propose that medications which inhibit the RAS ACE-dependent pathway may be beneficial in treating COVID-19 and should be explored in animal models and clinical trials. Here we give an overview of the RAS pathway with respect to COVID-19 and argue that strategies which manipulate this pathway might reduce the destructive lung manifestations of COVID-19 and improve patient outcomes.


ACE inhibitors, AT1 receptor blockers and COVID-19: clinical epidemiology evidences for a continuation of treatments. The ACER-COVID study

Abstract: Aims: The question of interactions between the renin angiotensin aldosterone system drugs and the incidence and prognosis of COVID-19 infection has been raised by the medical community. We hypothesised that if patients treated with ACE inhibitors (ACEI) or AT1 receptor blockers (ARB) were more prone to SARS-CoV2 infection and had a worse prognosis than untreated patients, the prevalence of consumption of these drugs would be higher in patients with COVID-19 compared to the general population. Methods and results: We used a clinical epidemiology approach based on the estimation of standardised prevalence ratio (SPR) of consumption of ACEI and ARB in four groups of patients (including 187 COVID-19 positive) with increasing severity referred to the University hospital of Lille and in three French reference samples (the exhaustive North population (n=1,569,968), a representative sample of the French population (n=414,046), a random sample of Lille area (n=1,584)). The SPRs of ACEI and ARB did not differ as the severity of the COVID-19 patients increased, being similar to the regular consumption of these drugs in the North of France population with the same non-significant increase for both treatment (1.17 [0.83-1.67]). A statistically significant increase in the SPR of ARB (1.56 [1.02-2.39]) was observed in intensive care unit patients only. After stratification on obesity, this increase was limited to the high risk subgroup of obese patients. Conclusions: Our results strongly support the recommendation that ACEI and ARB should be continued in the population and in COVID-19 positive patients, reinforcing the position of several scientific societies.


Mortality and use of angiotensin converting enzyme inhibitors in Covid 19 disease - a systematic review.

Abstract: Background. Interest exits concerning the use of angiotensin converting enzyme inhibitors (ACEi) in patients with Covid-19 disease. Objectives. To perform a systematic review on mortality associated to the use of ACEi in patients with Covid 19 disease. Methods. Search in Medline (PubMed) and in ISI Web of Knowledge; use of other sources. Results. A total of 19 articles were evaluated. Four studies were selected and used to produce the meta-analyses. These four studies involved a total number of 1.423 patients treated with ACEi and 11.868 not treated with ACEi. Significant heterogeneity was seen concerning mortality associated to the use of ACEi in the context of Covid-19 disease. One report showed significantly decreased mortality associated to ACEi use, but this finding was not confirmed by the three other studies. No significant difference in mortality was seen in the meta-analysis (ACEi users versus non-users; random effects; odds ratio, 0.93; 95% confidence interval [CI], 0.44 to 1.94; P=0.84). When compared to mortality in patients treated with angiotensin receptor blockers, mortality of patients treated with ACEi was not significantly different, although a trend was noted to exist (odds ratio, 0.74; 95% confidence interval [CI], 0.41 to 1.34; P=0.32). The population studied in the report showing decreased mortality associated to ACEi use had a mean age under 50 years, whereas two other reports had a mean or median patient age over 60 years. Conclusions. The data now presented argue in favor of carrying out clinical trials studying ACEi in Covid-19 patients, to explore the hypothesis that ACEi use has a protective effect in populations with a mean age under 50 years, but not necessarily in those with a mean age over 60 years.


Kidney and Lung ACE2 expression after an ACE inhibitor or an Ang II receptor blocker: implications for COVID-19

Abstract: Background There have been concerns that ACE inhibitors and Ang II receptor blockers may cause an increase in ACE2, the main receptor for SARs-CoV-2. Methods Kidneys from two genetic models of kidney ACE ablation and mice treated with captopril or telmisartan were used to examine ACE2 in isolated kidney and lung membranes. Results In a global ACE KO mice, ACE2 protein abundance in kidney membranes was reduced to 42 % of wild type, p < 0.05. In ACE 8/8 mice that over-expresses cardiac ACE protein but also has no kidney ACE expression, ACE2 protein in kidney membranes was also decreased (38 % of the WT, p<0.01). In kidney membranes from mice that received captopril or telmisartan for 2 weeks there was a reduction in ACE2 protein (37% in captopril treated p<0.01) and 76% in telmisartan treated p <0.05). In lung membranes the expression of ACE2 was very low and not detected by western blotting but no significant differences in terms of ACE2 activity could be detected in mice treated with captopril (118% of control) or telmisartan (93% of control). Conclusions Genetic kidney ACE protein deficiency, suppressed enzymatic activity by Captopril or blockade of the AT1 receptor with telmisartan are all associated with a decrease in ACE2 in kidney membranes. ACE2 protein in kidney or lungs is decreased or unaffected by RAS blockers indicating that these medications can not pose a risk for SARS-CoV-2 infection related to amplification of ACE2 at these two target sites for viral entry.


Renin-angiotensin-aldosterone system inhibitors and COVID-19 infection or hospitalization: a cohort study

Abstract: There are plausible mechanisms by which angiotensin-converting enzyme inhibitors (ACEIs) and angiotensin receptor blockers (ARBs) may increase the risk of COVID-19 infection or affect disease severity. To examine the association between these medications and COVID-19 infection or hospitalization, we conducted a retrospective cohort study within a US integrated healthcare system. Among people aged [≥]18 years enrolled in the health plan for at least 4 months as of 2/29/2020, current ACEI and ARB use was identified from pharmacy data, and the estimated daily dose was calculated and standardized across medications. COVID-19 infections were identified through 6/14/2020 from laboratory and hospitalization data. We used logistic regression to estimate adjusted odds ratios (ORs) and 95% confidence intervals. Among 322,044 individuals, 720 developed COVID-19 infection. Among people using ACEI/ARBs, 183/56,105 developed COVID-19 (3.3 per 1000 individuals) compared with 537/265,939 without ACEI/ARB use (2.0 per 1000), yielding an adjusted OR of 0.94 (95% CI 0.75-1.16). For use of < 1 defined daily dose vs. nonuse, the adjusted OR for infection was 0.89 (95% CI 0.62-1.26); for 1 to < 2 defined daily doses, 0.97 (95% CI 0.71-1.31); and for [≥]2 defined daily doses, 0.94 (95% CI 0.72-1.23). The OR was similar for ACEIs and ARBs and in subgroups by age and sex. 29% of people with COVID-19 infection were hospitalized; the adjusted OR for hospitalization in relation to ACEI/ARB use was 0.92 (95% CI 0.54-1.57), and there was no association with dose. These findings support current recommendations that individuals on these medications continue their use.


Treatment of patients with COVID-19 and concomitant cardiovascular diseases: Do not Forget about the Principles of Evidence-based Medicine/ Лечение больных с COVID-19 и сопутствующими сердечно-сосудистыми заболеваниями: не забывать о принципах доказательной медицины

Abstract: The recent discussion about the dangers of using angiotensin-converting-enzyme (ACE) inhibitors and angiotensin II receptor antagonists (ARA) in patients with COVID-19 is analyzed in the article. There is controversy over the hypothesis that these drugs can be factors contributing to an unfavorable outcome of a viral disease, as well as the absence of any clinical evidence for this hypothesis. The opinion that withdrawal of ACE inhibitors and ARA in patients with COVID-19 may increase the risk of adverse outcomes is presented.


[Renin-angiotensin-aldosterone blockers and Covic-19 infection : friends or enemies ?]

Abstract: ACE2 is not only an enzyme that counters the effects of the renin-angiotensin-aldosterone system (RAAS) but is also the entry receptor for SARS-CoV-2, the virus of the Covid-19 pandemic. Some experimental data suggest that ACE inhibitors and ARBs increase ACE2 levels, thus raising concerns on their security in Covid-19 positive patients. However, some studies have shown protection by these drugs in lower tract respiratory infections and ARDS. The actual consensus is to continue the treatment with RAAS inhibitors, abrupt withdrawal, especially in patients with cardiac or renal conditions, being hazardous in terms of cardiovascular outcomes, except in patients hospitalized in intensive care with hemodynamic instability. This position statement is actually unanimous among all international learned societies.


Angiotensin-converting enzyme 2 in severe acute respiratory syndrome coronavirus and SARS-CoV-2: A double-edged sword?

Abstract: Human angiotensin-converting enzyme 2 (ACE2) facilitates cellular entry of severe acute respiratory syndrome coronavirus (SARS-CoV) and SARS-CoV-2 as their common receptor. During infection, ACE2-expressing tissues become direct targets, resulting in serious pathological changes and progressive multiple organ failure or even death in severe cases. However, as an essential component of renin-angiotensin system (RAS), ACE2 confers protective effects in physiological circumstance, including maintaining cardiovascular homeostasis, fluid, and electrolyte balance. The absence of protective role of ACE2 leads to dysregulated RAS and thus acute changes under multiple pathological scenarios including SARS. This potentially shared mechanism may also be the molecular explanation for pathogenesis driven by SARS-CoV-2. We reasonably speculate several potential directions of clinical management including host-directed therapies aiming to restore dysregulated RAS caused by ACE2 deficiency. Enriched knowledge of ACE2 learned from SARS and COVID-19 outbreaks can provide, despite their inherent tragedy, informative clues for emerging pandemic preparedness.


Renin-Angiotensin-Aldosterone System Inhibitors and Risk of Covid-19

Abstract: BACKGROUND: There is concern about the potential of an increased risk related to medications that act on the renin-angiotensin-aldosterone system in patients exposed to coronavirus disease 2019 (Covid-19), because the viral receptor is angiotensin-converting enzyme 2 (ACE2). METHODS: We assessed the relation between previous treatment with ACE inhibitors, angiotensin-receptor blockers, beta-blockers, calcium-channel blockers, or thiazide diuretics and the likelihood of a positive or negative result on Covid-19 testing as well as the likelihood of severe illness (defined as intensive care, mechanical ventilation, or death) among patients who tested positive. Using Bayesian methods, we compared outcomes in patients who had been treated with these medications and in untreated patients, overall and in those with hypertension, after propensity-score matching for receipt of each medication class. A difference of at least 10 percentage points was prespecified as a substantial difference. RESULTS: Among 12,594 patients who were tested for Covid-19, a total of 5894 (46.8%) were positive; 1002 of these patients (17.0%) had severe illness. A history of hypertension was present in 4357 patients (34.6%), among whom 2573 (59.1%) had a positive test; 634 of these patients (24.6%) had severe illness. There was no association between any single medication class and an increased likelihood of a positive test. None of the medications examined was associated with a substantial increase in the risk of severe illness among patients who tested positive. CONCLUSIONS: We found no substantial increase in the likelihood of a positive test for Covid-19 or in the risk of severe Covid-19 among patients who tested positive in association with five common classes of antihypertensive medications.


Inhibitors of the renin-angiotensin system: The potential role in the pathogenesis of COVID-19

Abstract: Coronavirus disease 2019 (COVID-19), which initially began in China, has spread to other countries of Asia, Europe, America, Africa and Oceania, with the number of confirmed cases and suspected cases increasing each day. According to recently published research, it was found that the majority of the severe cases were elderly, and many of them had at least one chronic disease, especially cardiovascular diseases. Angiotensin-converting enzyme inhibitors/angiotensin receptor blockers (ACEIs/ARBs) are the most widely used drugs for cardiovascular diseases. The clinical effect of ACEIs/ARBs on patients with COVID-19 is still uncertain. This paper describes their potential role in the pathogenesis of COVID-19, which may provide useful in the advice of cardiologists and physicians.


[Role of age, comorbidity and renin- angiotensin-aldosterone system in COVID-19. Effects of ACE inhibitors and angiotensin receptor blockers]

Abstract: The review addressed the relationship of coronavirus disease 2019 (COVID-19) with functioning of the renin-angiotensin-aldosterone axis and the causes for unfavorable prognosis depending on patients' age and comorbidities. The authors discussed in detail potential effects of angiotensin-converting enzyme inhibitors and angiotensin II type 1 receptor antagonists on the risk of infection and the course of COVID-2019 as well as the effect of SARS-COV2 virus on the cardiovascular system.


The role of angiotensin-converting enzyme 2 in coronaviruses/influenza viruses and cardiovascular disease

Abstract: Angiotensin-converting enzyme 2 (ACE2) has emerged as a key regulator of the renin-angiotensin system in cardiovascular (CV) disease and plays a pivotal role in infections by coronaviruses and influenza viruses. The present review is primarily focused on the findings to indicate the role of ACE2 in the relationship of coronaviruses and influenza viruses to CV disease. It is postulated that the risk of coronavirus or influenza virus infection is high, at least partly due to high ACE2 expression in populations with a high CV risk. Coronavirus and influenza virus vaccine usage in high CV risk populations could be a potential strategy to prevent both CV disease and coronavirus/influenza virus infections.


Long-Term ACE Inhibitor/ARB Use Is Associated with Severe Renal Dysfunction and Acute Kidney Injury in Patients with severe COVID-19: Results from a Referral Center Cohort in the North East of France

Abstract: BACKGROUND: In patients with severe COVID-19, data are scarce and conflicting regarding whether chronic use of angiotensin-converting enzyme inhibitor (ACEI) or angiotensin receptor blocker (ARB) influences disease outcomes. In patients with severe COVID-19, we assessed the association between chronic ACEI/ARB use and the occurrence of kidney, lung, heart, and liver dysfunctions and the severity of the inflammatory reaction as evaluated by biomarkers kinetics, and their association with disease outcomes. METHODS: We performed a retrospective longitudinal cohort study on consecutive patients with newly diagnosed severe COVID-19. Independent predictors were assessed through receiver operating characteristic analysis, time-series analysis, logistic regression analysis, and multilevel modeling for repeated measures. RESULTS: On the 149 patients included in the study 30% (44/149) were treated with ACEI/ARB. ACEI/ARB use was independently associated with the following biochemical variations: phosphorus >40 mg/L (odds ratio [OR], 3.35, 95% CI, 1.83-6.14), creatinine >10.1 mg/L (OR, 3.22, 2.28-4.54), and urea nitrogen (UN) >0.52 g/L (OR, 2.65, 1.89-3.73). ACEI/ARB use was independently associated with acute kidney injury, AKI stage ≥1 (OR, 3.28, 2.17-4.94). The daily dose of ACEI/ARB was independently associated with altered kidney markers with an increased risk of +25 to +31% per each 10 mg increment of lisinopril-dose equivalent. In multivariable multilevel modeling, UN >0.52 g/L was independently associated with the risk of acute respiratory failure (OR, 3.54, 1.05-11.96). CONCLUSIONS: Patients chronically treated with ACEI/ARB who have severe COVID-19 are at increased risk of acute kidney injury. In these patients, the increase in UN associated with ACEI/ARB use could predict the development of acute respiratory failure.


Renin-Angiotensin System Blockers and the COVID-19 Pandemic: At Present There Is No Evidence to Abandon Renin-Angiotensin System Blockers

Abstract: During the spread of the severe acute respiratory syndrome coronavirus-2, some reports of data still emerging and in need of full analysis indicate that certain groups of patients are at risk of COVID-19. This includes patients with hypertension, heart disease, diabetes mellitus, and clearly the elderly. Many of those patients are treated with renin-angiotensin system blockers. Because the ACE2 (angiotensin-converting enzyme 2) protein is the receptor that facilitates coronavirus entry into cells, the notion has been popularized that treatment with renin-angiotensin system blockers might increase the risk of developing a severe and fatal severe acute respiratory syndrome coronavirus-2 infection. The present article discusses this concept. ACE2 in its full-length form is a membrane-bound enzyme, whereas its shorter (soluble) form circulates in blood at very low levels. As a mono-carboxypeptidase, ACE2 contributes to the degradation of several substrates including angiotensins I and II. ACE (angiotensin-converting enzyme) inhibitors do not inhibit ACE2 because ACE and ACE2 are different enzymes. Although angiotensin II type 1 receptor blockers have been shown to upregulate ACE2 in experimental animals, the evidence is not always consistent and differs among the diverse angiotensin II type 1 receptor blockers and differing organs. Moreover, there are no data to support the notion that ACE inhibitor or angiotensin II type 1 receptor blocker administration facilitates coronavirus entry by increasing ACE2 expression in either animals or humans. Indeed, animal data support elevated ACE2 expression as conferring potential protective pulmonary and cardiovascular effects. In summary, based on the currently available evidence, treatment with renin-angiotensin system blockers should not be discontinued because of concerns with coronavirus infection.


Response by Cohen et al to Letter Regarding Article, "Association of Inpatient Use of Angiotensin-Converting Enzyme Inhibitors and Angiotensin II Receptor Blockers With Mortality Among Patients With Hypertension Hospitalized With COVID-19"


Physiological and pathological regulation of ACE2, the SARS-CoV-2 receptor

Abstract: The renin-angiotensin system (RAS) is crucial for the physiology and pathology of all the organs. Angiotensin-converting enzyme 2 (ACE2) maintains the homeostasis of RAS as a negative regulator. Recently, ACE2 was identified as the receptor of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the coronavirus that is causing the pandemic of Coronavirus disease 2019 (COVID-19). Since SARS-CoV-2 must bind with ACE2 before entering the host cells in humans, the distribution and expression of ACE2 may be critical for the target organ of the SARS-CoV-2 infection. Moreover, accumulating evidence has demonstrated the implication of ACE2 in the pathological progression in tissue injury and several chronic diseases, ACE2 may also be essential in the progression and clinical outcomes of COVID-19. Therefore, we summarized the expression and activity of ACE2 in various physiological and pathological conditions, and discussed its potential implication in the susceptibility of SARS-CoV-2 infection and the progression and prognosis of COVID-19 patients in the current review.


Angiotensin receptor blockers and COVID-19

Abstract: Angiotensin Receptor Blockers (ARBs) exhibit major pleiotropic protecting effects beyond their antihypertensive properties, including reduction of inflammation. ARBs directly protect the lung from the severe acute respiratory syndrome as a result of viral infections, including those from coronavirus. The protective effect of ACE2 is enhanced by ARB administration. For these reasons ARB therapy must be continued for patients affected by hypertension, diabetes and renal disease, comorbidities of the current COVID-19 pandemic. Controlled clinical studies should be conducted to determine whether ARBs may be included as additional therapy for COVID-19 patients.


SARS-CoV2: should inhibitors of the renin-angiotensin system be withdrawn in patients with COVID-19?


Coronavirus disease 2019 (COVID-19) and the renin-angiotensin system: A closer look at angiotensin-converting enzyme 2 (ACE2)

Abstract: Since the first cases of atypical pneumonia linked to the Huanan Seafood Wholesale Market in Wuhan, China, were described in late December 2019, the global landscape has changed radically. In March 2020, the World Health Organization declared COVID-19 a global pandemic, and at the time of writing this review, just over three million individuals have been infected with more than 200,000 deaths globally. Numerous countries are in 'lockdown', social distancing is the new norm, even the most advanced healthcare systems are under pressure, and a global economic recession seems inevitable. A novel coronavirus (SARS-CoV-2) was identified as the aetiological agent. From experience with previous coronavirus epidemics, namely the severe acute respiratory syndrome (SARS) and Middle East Respiratory Syndrome (MERS) in 2004 and 2012 respectively, it was postulated that the angiotensin-converting enzyme-2 (ACE2) receptor is a possible port of cell entry. ACE2 is part of the renin-angiotensin system and is also associated with lung and cardiovascular disorders and inflammation. Recent studies have confirmed that ACE2 is the port of entry for SARS-CoV-2. Male sex, advanced age and a number of associated comorbidities have been identified as risk factors for infection with COVID-19. Many high-risk COVID-19 patients with comorbidities are on ACE inhibitors and angiotensin receptor blockers, and this has sparked debate about whether to continue these treatment regimes. Attention has also shifted to ACE2 being a target for future therapies or vaccines against COVID-19. In this review, we discuss COVID-19 and its complex relationship with ACE2.


Angiotensin-converting enzyme inhibitors and angiotensin II receptor blockers are not associated with severe COVID-19 infection in a multi-site UK acute hospital trust

Abstract: AIMS: The SARS-CoV-2 virus binds to the angiotensin-converting enzyme 2 (ACE2) receptor for cell entry. It has been suggested that angiotensin-converting enzyme inhibitors (ACEi) and angiotensin II receptor blockers (ARB), which are commonly used in patients with hypertension or diabetes and may raise tissue ACE2 levels, could increase the risk of severe COVID-19 infection. METHODS AND RESULTS: We evaluated this hypothesis in a consecutive cohort of 1200 acute inpatients with COVID-19 at two hospitals with a multi-ethnic catchment population in London (UK). The mean age was 68 ± 17 years (57% male) and 74% of patients had at least one comorbidity. Overall, 415 patients (34.6%) reached the primary endpoint of death or transfer to a critical care unit for organ support within 21 days of symptom onset. A total of 399 patients (33.3%) were taking ACEi or ARB. Patients on ACEi/ARB were significantly older and had more comorbidities. The odds ratio for the primary endpoint in patients on ACEi and ARB, after adjustment for age, sex and co-morbidities, was 0.63 (95% confidence interval 0.47-0.84, P < 0.01). CONCLUSIONS: There was no evidence for increased severity of COVID-19 in hospitalised patients on chronic treatment with ACEi or ARB. A trend towards a beneficial effect of ACEi/ARB requires further evaluation in larger meta-analyses and randomised clinical trials.


Use of renin-angiotensin-aldosterone system inhibitors and risk of COVID-19 requiring admission to hospital: a case-population study

Abstract: BACKGROUND: Concerns have been raised about the possibility that inhibitors of the renin-angiotensin-aldosterone system (RAAS) could predispose individuals to severe COVID-19; however, epidemiological evidence is lacking. We report the results of a case-population study done in Madrid, Spain, since the outbreak of COVID-19. METHODS: In this case-population study, we consecutively selected patients aged 18 years or older with a PCR-confirmed diagnosis of COVID-19 requiring admission to hospital from seven hospitals in Madrid, who had been admitted between March 1 and March 24, 2020. As a reference group, we randomly sampled ten patients per case, individually matched for age, sex, region (ie, Madrid), and date of admission to hospital (month and day; index date), from Base de datos para la Investigación Farmacoepidemiológica en Atención Primaria (BIFAP), a Spanish primary health-care database, in its last available year (2018). We extracted information on comorbidities and prescriptions up to the month before index date (ie, current use) from electronic clinical records of both cases and controls. The outcome of interest was admission to hospital of patients with COVID-19. To minimise confounding by indication, the main analysis focused on assessing the association between COVID-19 requiring admission to hospital and use of RAAS inhibitors compared with use of other antihypertensive drugs. We calculated odds ratios (ORs) and 95% CIs, adjusted for age, sex, and cardiovascular comorbidities and risk factors, using conditional logistic regression. The protocol of the study was registered in the EU electronic Register of Post-Authorisation Studies, EUPAS34437. FINDINGS: We collected data for 1139 cases and 11â390 population controls. Among cases, 444 (39·0%) were female and the mean age was 69·1 years (SD 15·4), and despite being matched on sex and age, a significantly higher proportion of cases had pre-existing cardiovascular disease (OR 1·98, 95% CI 1·62-2·41) and risk factors (1·46, 1·23-1·73) than did controls. Compared with users of other antihypertensive drugs, users of RAAS inhibitors had an adjusted OR for COVID-19 requiring admission to hospital of 0·94 (95% CI 0·77-1·15). No increased risk was observed with either angiotensin-converting enzyme inhibitors (adjusted OR 0·80, 0·64-1·00) or angiotensin-receptor blockers (1·10, 0·88-1·37). Sex, age, and background cardiovascular risk did not modify the adjusted OR between use of RAAS inhibitors and COVID-19 requiring admission to hospital, whereas a decreased risk of COVID-19 requiring admission to hospital was found among patients with diabetes who were users of RAAS inhibitors (adjusted OR 0·53, 95% CI 0·34-0·80). The adjusted ORs were similar across severity degrees of COVID-19. INTERPRETATION: RAAS inhibitors do not increase the risk of COVID-19 requiring admission to hospital, including fatal cases and those admitted to intensive care units, and should not be discontinued to prevent a severe case of COVID-19. FUNDING: Instituto de Salud Carlos III.


Angiotensin-converting enzyme inhibitors, angiotensin II receptor blockers and coronavirus


Ramipril in High Risk Patients with COVID-19

Abstract: BACKGROUND: The coronavirus disease 2019 (COVID-19) is caused by SARS-CoV2 that interfaces with the renin-angiotensin-aldosterone system (RAAS) through angiotensin-converting enzyme 2 (ACE-2). This interaction has been proposed as a potential risk factor in patients treated with RAAS-inhibitors. OBJECTIVES: To analyze if RAAS-inhibitors modify the risk for COVID-19. METHODS: RASTAVI (NCT03201185) is an ongoing randomized clinical trial randomly allocating Ramipril or control after successful transcatheter aortic valve replacement at 14 centers is Spain. We performed a non-pre-specified interim analysis to evaluate its impact on COVID-19 risk in this vulnerable population. RESULTS: As in April 1st 2020, 102 patients (50 Ramipril and 52 controls) were included in the trial. Mean age was 82.3±6.1 years, 56.9% males. Median time of Ramipril treatment was 6 months [IQR:2.9-11.4]. Eleven patients (10.8%) have been diagnosed with COVID-19 (6 in control group and 5 receiving Ramipril, HR=1.150 [95%CI: 0.351-3.768]). The risk of COVID-19 was increased in older patients (p=0.019), those with atrial fibrillation (p=0.066), lower hematocrit (p=0.084), and more comorbidities according to Society of thoracic surgeons score (p=0.065). Admission and oxygen supply was required in 4.9% (2 patients in the Ramipril and 3 in control), and 4 of them died (two in each randomized group). A higher body mass index was the only factor increasing the mortality rate (p=0.039). CONCLUSIONS: In a high risk population of old patients with cardiovascular disease, randomization to Ramipril had no impact in the incidence or severity of COVID-19. This analysis supports the maintenance of RAAS-inhibitor treatment during COVID-19 crisis.


Continuing versus suspending angiotensin-converting enzyme inhibitors and angiotensin receptor blockers: Impact on adverse outcomes in hospitalized patients with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)--The BRACE CORONA Trial

Abstract: Angiotensin-converting enzyme-2 (ACE2) expression may increase due to upregulation in patients using angiotensin-converting enzyme inhibitors (ACEI) and angiotensin receptor blockers (ARBs). Because renin-angiotensin system blockers increase levels of ACE2, a protein that facilitates coronavirus entry into cells, there is concern that these drugs could increase the risk of developing a severe and fatal form of COVID-19. The impact of discontinuing ACEI and ARBs in patients with COVID-19 remains uncertain. DESIGN: BRACE CORONA is a pragmatic, multicenter, randomized, phase IV, clinical trial that aims to enroll around 500 participants at 34 sites in Brazil. Participants will be identified from an ongoing national registry of suspected and confirmed cases of COVID-19. Eligible patients using renin-angiotensin system blockers (ACEI/ARBs) with a confirmed diagnosis of COVID-19 will be randomized to a strategy of continued ACEI/ARB treatment versus temporary discontinuation for 30 days. The primary outcome is the median days alive and out of the hospital at 30 days. Secondary outcomes include progression of COVID-19 disease, all-cause mortality, death from cardiovascular causes, myocardial infarction, stroke, transient ischemic attack, new or worsening heart failure, myocarditis, pericarditis, arrhythmias, thromboembolic events, hypertensive crisis, respiratory failure, hemodynamic decompensation, sepsis, renal failure, and troponin, B-type natriuretic peptide (BNP), N-terminal-proBNP, and D-dimer levels. SUMMARY: BRACE CORONA will evaluate whether the strategy of continued ACEI/ARB therapy compared with temporary discontinuation of these drugs impacts clinical outcomes among patients with COVID-19.


Angiotensin-Converting Enzyme Inhibitors and Angiotensin Receptor Blockers in Patients With Coronavirus Disease 2019: Friend or Foe?

Abstract: When the coronavirus disease 2019 (COVID-19) wreaked an unprecedented havoc of an escalating number of deaths and hospitalization in the United States, clinicians were faced with a myriad of unanswered questions, one of the them being the implication of the renin-angiotensin-aldosterone system in patients with COVID-19. Animal data and human studies have shown that angiotensin-converting enzyme (ACE) inhibitors and angiotensin receptor blockers (ARBs) increase the expression of ACE2. ACE2 is an enzyme found in the heart, kidney, gastrointestinal tract, and lung and is a coreceptor for severe acute respiratory syndrome-related coronavirus-2 (SARS-CoV2), the virus responsible for COVID-19. Therefore, one can speculate that discontinuing ACE inhibitor or ARB therapy may lead to decreased ACE2 expression, thereby attenuating the infectivity of SARS-CoV-2, and mitigating the disease progression of COVID-19. However, several studies have also shown that ACE2 exhibits reno- and cardioprotection and preserves lung function in acute respiratory distress syndrome, which would favor ACE inhibitor or ARB therapy. This article is to examine and summarize the 2 opposing viewpoints and provide guideline recommendations to support the use or discontinuation of ACE inhibitors and ARBs in patients with COVID-19.


Angiotension-converting enzyme inhibitors and angiotensin-receptor blockers are not associated with increased risk of SARS-CoV-2 infection

Abstract: In a large Israeli dataset of 14 520 individuals tested for SARS-CoV-2, angiotension-converting enzyme inhibitors and angiotensin-receptor blockers were not found to be associated with increased SARS-CoV-2 infection after adjusting for major confounders. Patients on these medications should not stop their medication prophylactically.


Overview of Covid-19 regarding the cardiovascular situation in the light of current reports

Abstract: Nowadays coronavirus disease 2019 (Covid-19) is increasing mortality all over the world mercilessly. We are learning almost every day about its new symptoms and that it mutates quickly. This disease ties us up and leaves us desperate. Death from this disease has increased in patients who had with pre-existing medical conditions, especially cardiovascular ones, by eliminating the angiotensin-converting enzyme (ACE)-2 receptor in the lungs. Also, ACE1 and angiotensin receptor blockers (ARB) may stimulate ACE2 expression and worse the prognosis. Intravenous infusions of ACEIs and ARBs in experimental animals increase the numbers of ACE2 receptors. So, it may be one of the reasons that COVID-19 infects the cells of patients treating hypertension. However, most of the congress of cardiology do not recommend discontinue of these anti-hypertensive drugs. Therefore, this brief report evaluates Covid-19 in the view of cardiovascular diseases taking into account current reports and suggests some possible solutions to keep the virus under control.


Renin-Angiotensin-System (RAS) und COVID-19  Zur Verordnung von RAS-Blockern./ [Renin-Angiotensin-System (RAS) and COVID-19 - On The Prescription of RAS Blockers]

Abstract: Twenty years ago, an enzyme homologous to the previously known angiotensin-converting enzyme (ACE) was identified, and subsequently named ACE2. In the renin-angiotensin system (RAS), ACE2 has counter-regulatory functions against the classical effector peptide angiotensin II, for example in blood pressure regulation and cardiovascular remodeling. However, ACE2 provides an initially unexpected interesting link between virology and cardiovascular medicine. That is, ACE2 represents the binding receptor for the cellular uptake of SARS-CoV and SARS-CoV-2 viruses. Thus, ACE2 is relevant for COVID-19. In this context, it was suspected that therapy with RAS blockers might promote transmission and complications of COVID-19 by upregulation of ACE2 expression. The aim of this short review is, to describe the link between the RAS, particularly ACE2, and COVID-19. Based on our analysis and evaluation of the available findings, we justify our conclusion: important drugs such as ACE inhibitors and angiotensin receptor blockers should continue to be prescribed according to guidelines to stable patients in the context of the COVID-19 pandemic.


Drugs acting on renin angiotensin system and use in ill patients with COVID-19

Abstract: Some concerns about the prescription of drugs acting on the renin-angiotensin system (angiotensin-converting enzyme 1 (ACE1) inhibitors, ACEi; angiotensin II type 1 receptor blockers, ARB) have emerged due to SARS COV2 and COVID-19 pandemic. These very legitimate questions are directly the consequence of the recent recognition of the fundamental role of ACE2 (angiotensin-converting enzyme 2) in COVID-19 infection. Indeed, SARS COV2 utilizes ACE2 as a membrane receptor to enter target cells. Consequently, the putative impact of drugs modulating the renin-angiotensin system on the risk of developing severe or fatal severe acute respiratory syndrome in case of COVID-19 infection emerged. As a membrane-bound enzyme (carboxypeptidase), ACE2 inactivates angiotensin II and therefore physiologically counters its effects. Due to a different structure compared with ACE1, ACE2 is insensitive to ACEIs. In vitro, both ARBs and ACEi appear able to upregulate ACE2 tissue expression and activity but these results were not confirmed in Humans. The exact impact of both ARBs and ACEis on COVID-19 infection is definitively known and preliminary results are even in favor of a protective role confers by these drugs. Due to the crucial role of ACE2, some groups support the hypothesis that a modulation of ACE2 expression could represent a valuable therapeutic target could confer protective properties against inflammatory tissue damage in COVID-19 infection. So, studies are currently ongoing to test the impact of elevated ACE2 membrane expression, administration of ARB and infusion of soluble ACE2. In summary, based on the currently available evidences and as recommended by several medical societies, ACEi or ARB should not be systematically discontinued because to date no safety signal was raised with the use of these drugs.


Comparative impacts of angiotensin converting enzyme inhibitors versus angiotensin II receptor blockers on the risk of COVID-19 mortality

Abstract: N/A.


Outbreak of SARS-CoV2: Pathogenesis of infection and cardiovascular involvement

Abstract: Since the new severe acute respiratory syndrome coronavirus 2 (SARS-CoV2) has emerged from China, the infection (novel corona virus disease-2019, COVID-19) has affected many countries and led to many deaths worldwide. Like SARS-CoV, angiotencin converting enzyme (ACE)2 as a functional receptor for SARS-CoV2 is essential for the virus to make an entry into the cell. ACE2 is a part of Renin-Angiotensin-Aldosterone System, which is expressed in several organs that opposes the angiotensin (Ang) II functions by converting Ang II to Ang (1-7), the one with vasodilation effects. The death rate of COVID-19 is estimated to be approximately 3.4%; however, some comorbid conditions like underlying cardiovascular disease, hypertension, and diabetes increase the risk of mortality. In addition, cardiovascular involvement as a complication of SARS-CoV2 could be direct through either ACE2 receptors that are expressed tremendously in the heart, or by the surge of different cytokines or by acute respiratory distress syndrome-induced hypoxia. Traditional risk factors could aggravate the process of COVID-19 infection that urges the triage of these high-risk patients for SARS-CoV2. Currently, there is no effective, proven treatment or vaccination for COVID-19, but many investigators are struggling to find a treatment strategy as soon as possible. Some potential medications like chloroquine by itself or in combination with azithromycin and some protease inhibitors used for the treatment of COVID-19 have cardiovascular adverse effects, which should be kept in mind while the patients taking these medications are being closely monitored.


SARS-CoV-2 receptor ACE2-dependent implications on the cardiovascular system: From basic science to clinical implications

Abstract: The current COVID-19 pandemic started several months ago and is still exponentially growing in most parts of the world - this is the most recent and alarming update. COVID-19 requires the collaboration of nearly 200 countries to curb the spread of SARS-CoV-2 while gaining time to explore and improve treatment options especially for cardiovascular disease (CVD) and immunocompromised patients, who appear to be at high-risk to die from cardiopulmonary failure. Currently unanswered questions are why elderly people, particularly those with pre-existing comorbidities seem to exhibit higher mortality rates after SARS-CoV-2 infection and whether intensive care becomes indispensable for these patients to prevent multi-organ failure and sudden death. To face these challenges, we here summarize the molecular insights into viral infection mechanisms and implications for cardiovascular disease. Since the infection starts in the upper respiratory system, first flu-like symptoms develop that spread throughout the body. The wide range of affected organs is presumably based on the common expression of the major SARS-CoV-2 entry-receptor angiotensin-converting enzyme 2 (ACE2). Physiologically, ACE2 degrades angiotensin II, the master regulator of the renin-angiotensin-aldosterone system (RAAS), thereby converting it into vasodilatory molecules, which have well-documented cardio-protective effects. Thus, RAAS inhibitors, which may increase the expression levels of ACE2, are commonly used for the treatment of hypertension and CVD. This, and the fact that SARS-CoV-2 hijacks ACE2 for cell-entry, have spurred controversial discussions on the role of ACE2 in COVID-19 patients. In this review, we highlight the state-of-the-art knowledge on SARS-CoV-2-dependent mechanisms and the potential interaction with ACE2 expression and cell surface localization. We aim to provide a list of potential treatment options and a better understanding of why CVD is a high risk factor for COVID-19 susceptibility and further discuss the acute as well as long-term cardiac consequences.


Good or bad: Application of RAAS inhibitors in COVID-19 patients with cardiovascular comorbidities

Abstract: The coronavirus disease 2019 (COVID-19) pandemic is caused by a newly emerged coronavirus (CoV) called Severe Acute Respiratory Syndrome coronavirus 2 (SARS-CoV-2). COVID-19 patients with cardiovascular disease (CVD) comorbidities have significantly increased morbidity and mortality. The use of angiotensin-converting enzyme (ACE) inhibitors and angiotensin II receptor type 1 blockers (ARBs) improve CVD outcomes; however, there is concern that they may worsen the prognosis of CVD patients that become infected with SARS-CoV-2 because the virus uses the ACE2 receptor to bind to and subsequently infect host cells. Thus, some health care providers and media sources have questioned the continued use of ACE inhibitors and ARBs. In this brief review, we discuss the effect of ACE inhibitor-induced bradykinin on the cardiovascular system, on the renin-angiotensin-aldosterone system (RAAS) regulation in COVID-19 patients, and analyze recent clinical studies regarding patients treated with RAAS inhibitors. We propose that the application of RAAS inhibitors for COVID-19 patients with CVDs may be beneficial rather than harmful.