bluuebunny/crossref_metadata_2025 huggingface dataset:
Environmental Factors Contributing to Antibiotic Resistance
Authors: Phillips Ian
Published: August 2016

The genetic determinants of antibiotic resistance originate as a result of random events, affected only by those physical and chemical agents that stimulate mutation. It is the selection and spread, within and between species, of new genetic material that is influenced by environmental factors, though the intrinsic antibiotic resistance of many opportunistic pathogens remains to be explained.

Depending on the frequency of genetic change, the biochemical resistance mechanism, the efficiency of selection (including access of antibiotic to relevant bacteria), and the opportunity for person-to-person spread, resistance may present in a number of ways. The use of an antibiotic in any individual may give rise to resistance, among pathogens or normal flora, to that antibiotic alone, to some or all members of its class, or to additional unrelated antibacterials, or to the acquisition of new bacteria, from a variety of sources (humans, animals, inanimate environment). A resistant organism may occasionally have other advantages that enable it to spread in the absence of the initial selective agents.

In the absence of controlled experiments, which are difficult or perhaps impossible, the only evidence of the truth of these hypotheses comes from the clinical use of antibiotics. A wise observer will conclude that the emergence of resistance is a rare event in an individual patient, but is commoner but by no means universal in populations, especially those that are closed. He will note the reports of diminished resistance in the presence of increased usage.

The role of academic infection control is to explain all the phenomena observed, and to formulate methods for identifying and countering the actual as opposed to the imagined hazards.
Hygienic Hand Disinfection
Authors: Rotter M.L.
Published: August 2016

The purpose of hygienic hand disinfection is to render hands safe after contact with pathogens. Comparing effects of disinfection procedures on infection ratios is too difficult for routine purposes but the degerming efficacy may be determined in laboratory tests with volunteers. In the Vienna test model the efficacy of a specific procedure being tested is compared to that of a standard disinfection (rubbing into hands 3 ml of iso-propanol 60% v/v, 30 seconds, twice) tested in parallel with the same volunteers. This ensures standardization, thus comparability of results between laboratories, and provides the investigator with a yardstick for efficacy. The model includes artificial contamination, assessment of the release of test bacteria (E. ColiATCC 11229) before and after disinfection by the finger tip method, and addition of neutralizers to sampling fluids. Alcohols in appropriate concentrations are highly effective (log reductions: >4.0) whereas procedures employing disinfectant detergents act like soap (log reductions: ≤ 3.2) and may cause dissemination of pathogens.
Pseudobacteremia Traced to Cross-Contamination by an Automated Blood Culture Analyzer
Authors: Craven Donald E. , Lichtenberg Deborah A. , Browne Kathleen F. , Coffey Donna M. , Treadwell Thomas L. , McCabe William R.
Published: August 2016

Twenty-three episodes of pseudobacteremia occurring over a seven-month period were traced to cross-contamination by the automated blood culture analyzer (BACTEC 460) used in the microbiology laboratory. An epidemiologic investigation of an unusual cluster of three patients with pseudobacteremia caused by oxacillin-resistantStaphylococcus aureusled to the identification of the problem. Mock trials of the blood culture procedure confirmed that the blood culture analyzer was the source of contamination. After the needle sterilizer was replaced by the manufacturer, the problem of cross-contamination abated. Contamination of sterile blood cultures by an instrument intended to identify bacteremia rapidly may lead to incorrect diagnosis, unnecessary administration of antibiotics and prolonged hospitalization. Because of the widespread use of automated blood culture analyzers in the US, physicians, microbiologists, and infection control personnel should be alert to the possibility of cross-contamination and the subtle way in which it may present.
Recommendations for the Care of Automated Peritoneal Dialysis Machines: Can the Risk of Peritonitis Be Reduced?
Authors: Berkelman Ruth L. , Band Jeffery D. , Petersen Norman J.
Published: August 2016

Automated peritoneal dialysis systems have helped make intermittent peritoneal dialysis an alternative to hemodialysis for long-term management of patients with end-stage renal disease. However, if not cleaned and maintained properly, these machines provide a reservoir for pathogens. The microbiologic barriers in these machines are not impenetrable, but sterile dialy-sate fluid can be produced if the machines are adequately cleaned and disinfected. Potential shortcomings of the microbiologic barriers are discussed, and guidelines to prevent contamination of the internal parts of a machine are suggested.
Multidose Medication Vial Sterility: An In-Use Study and a Review of the Literature
Authors: Longfield Robert , Longfield Jenice , Smith L. Patrick , Hyams K. Craig , Strohmer M. Elena
Published: August 2016

Contaminated multiple-dose medication vials (MDV) have been implicated in transmission of bacterial infections. It has been suggested that MDV be discarded after 24 hours or even after a single use. At our hospital, we cultured 1,223 weekly samples from 864 MDV in-use over a three-month period. Medications included xylocaine, insulin, heparin, immunizations, and miscellaneous agents. None of the samples was culture-positive. The duration of use was 9.5d (median), 18d (mean), and 1-402d (range) with 13% of vials in-use for more than 30 days. The mean duration of use was significantly shorter for medicine wards, emergency room, and outpatient clinics than for surgery and obgyn wards (p<0.05). Heparin and insulin MDV were in-use for significantly less time than xylocaine and miscellaneous agents (p<0.05), and insulin MDV were more regularly dated (p=0.001). The percentage of undated MDV declined significantly by month during die study (p=0.003). These results lend support to our current guideline that MDV should be dated upon opening and that, unless visible or suspected contamination occurs, vials are discarded either when empty or at the manufacturer's expiration date.
The Pharmacology of Aminoglycosides—I. Considered as a Group
Authors: Norris Sandra M. , Ravdin Jonathan I.
Published: August 2016

This review of aminoglycoside pharmacology will appear in two parts. The first segment summarizes general information applicable to all agents, such as aspects of absorption, distribution, and clearance. The subsequent article will focus on specific agents currently in use in clinical practice: gentamicin, tobramycin, netilmicin, amikacin, streptomycin, and kanamycin, highlighting toxicities and pharmacokinetic-based dosing strategies.

Embedded in the history of antimicrobial agents with the discovery of streptomycin in 1944, the aminoglycosides remain a mainstay of contemporary antibiotic therapy. Noteworthy features include rapid bactericidal activity against aerobic gram-negative organisms as well as additive or synergistic activity when coadministered with beta-lactam agents. These positive attributes are offset by limited penetration into various body fluids and tissues, and dose (concentration) related renal and ototoxicity. Despite the proliferation of safer beta-lactam compounds with expanded antimicrobial spectrums, the aminoglycosides are still initial drugs of choice for most life-threatening, aerobic, gram-negative infections. Used in combination with anti-pseudomonal penicillins, the aminoglycosides are the agents of choice for empiric therapy of fever in the neutropenic host or documented tissue infection withPseudomonas aeruginosa.
Nosocomial Respiratory Infections
Authors: Dixon Richard E.
Published: August 2016

Nosocomial respiratory tract infections are major causes of excessive morbidity and mortality in US hospitals, affecting an estimated five to ten of every 1,000 patients. Patients with serious underlying diseases have an especially high risk of acquiring these infections, and that risk is magnified by exposure to respiratory therapy. Until recently, contaminated respiratory care devices were a major cause of infection, but procedures for the management of these devices have decreased their role substantially. Now, aspiration of oropharyngeal flora appears to be responsible for most cases of bacterial respiratory infections. Therefore, techniques to alter the flora of the oropharynx and to diminish the risk of aspiration are important priorities for infection control. Exposure to intensive care units (ICUs) is also a major risk factor for nosocomial pulmonary infection, and person-to-person spread of microorganisms within ICUs seems to be responsible for some of these infections.

Increasing numbers of pulmonary infections are being caused by newly identified or previously uncommon pathogens, and this shift requires that traditional control techniques be reevaluated to assure that they remain relevant.

Few new techniques have been developed recently to alter host susceptibility, prevent acquisition of virulent pathogens, or eradicate infectious organisms from their sources, but effective infection control programs in hospitals appear to reduce the incidence of nosocomial pulmonary infection, and implementation of these programs deserves serious consideration in all hospitals.
Infectious Waste
Authors: Rutala William A.
Published: August 2016

The exigency for a comprehensive infectious waste management program in hospitals is influenced by federal guidelines and concern about the public image of our hospitals as a source of environmental pollution. The need to discard infectious waste in an aesthetically acceptable manner that will prevent hazards from injury and/or infection has received some recognition, but many states have not promulgated regulations on infectious waste management. Realizing the critical environmental health problems posed by improper disposal of infectious and other hazardous waste, Congress charged the Environmental Protection Agency (EPA) with the responsibility of formulating “cradle-to-grave” regulations over hazardous waste by requiring implementation of Subtitle C of the Resource Conservation and Recovery Act of 1976. Waste with infectious characteristics that may “pose a substantial present or potential hazard to human health or the environment when improperly … managed” are considered by this Act as hazardous waste. While by definition infectious waste is considered a subset of hazardous waste, the EPA has not yet issued regulations to fulfill the Congressional mandate to establish a management system for infectious waste. It has, however, prepared a technical manual which is intended to assist hospitals and states so they may establish appropriate programs and/or regulations on infectious waste management. This commentary will review some of the principles, practices, problems, products and services associated with infectious waste management.
Infection Control Committee Minutes—Revisited
Authors: Nottebart Harry C.
Published: August 2016

In the first issue of Infection Control I discussed hospital infection control committee minutes and reports. Recently there have been cases involving hospital infection control committee minutes and reports, Sherman and Farley infra, and this information should be available to the infection control community. There are also two earlier cases that have bearing as precedents; these four cases will be discussed in chronological order.
Effect of Antiseptic Agents on Skin Flora of the Perineum of Men with Spinal Cord Injury
Authors: Gilmore Donna S. , Montgomerie John Z. , Graham Irene E. , Schick Donald G. , Jimenez Enes M.
Published: August 2016

Male patients with spinal cord injury are frequently colonized withP. aeruginosaandK. pneumoniaeon the perineum. Regular bathing with bar soap has not influenced this colonization. We have attempted to remove these bacteria using antiseptic agents. The number ofP. aeruginosa,K. pneumoniaeand total aerobic bacteria on the perineum and the penile shaft was determined before and after cleaning with bar soap, chlorhexidine, povidone-iodine and pHresh. Povidone-iodine and chlorhexidine had no advantage over bar soap or pHresh in the removal ofP. aeruginosaorK. pneumoniaefrom the perineum of patients with spinal cord injury.
Permeability of the Thermometer Sheath When Taking Oral Temperatures
Authors: Soltero Donald J. , Sommers Earl E. , Truelove Edmond L.
Published: August 2016

Oral mercury-in-glass thermometers are contaminated with each use and must be decontaminated prior to reuse. It has been shown that the application of a thermometer sheath prevents contamination of the rectal thermometer. The purpose of the present study is to evaluate sheathed thermometers for contamination after oral use on dentulous patients. One hundred sterile sheathed thermometers were distributed into four groups and subjected to in vitro and in vivo conditions.

After clinical use 80% of the sheathed thermometers became contaminated, while not one of those exposed to microorganisms in vitro was contaminated. The cause for contamination was shown to be perforation of the sheath by the dentition. Thus the thermometer sheath is ineffective in preventing contamination of the mercury-in-glass thermometer when used for obtaining oral temperatures from dentulous patients. Sheathed mercury-in-glass thermometers should be decontaminated after each oral use.
Prevalence of Cytomegalovirus Antibody in Nursing Personnel
Authors: Lipscomb Jane A. , Linnemann Calvin C. , Hurst Pei Fung , Myers Martin G. , Stringer William , Moore Peggy , Hammond Jean
Published: August 2016

To evaluate the risk to nurses of childbearing age of acquiring cytomegalovirus (CMV) infection during the care of patients at high risk of the infection, 374 female hospital employees (288 nursing personnel) were interviewed and screened for antibody to CMV. Fifty-six percent of the population surveyed had antibody to CMV as measured by an immunofluorescent assay. Among nursing personnel, analysis of antibody prevalence by job title, work area, and duration of work showed no association between seropositivity and either current or past exposure to “high-risk” patients, such as infants and immunosuppressed individuals. Age, race (non-white), and the number of pregnancies reported by participants were significantly associated with the presence of antibody. Among 73 employees of a children's hospital, the prevalence of CMV antibody was 41%. This survey suggests that hospital nursing is not a major risk factor for acquiring CMV infection. However, this finding needs further evaluation in a prospective study of seroconversion rates among seronegative nurses.
A Nursery Outbreak of Multiple-Aminoglycoside-ResistantEscherichia coli
Authors: Gaynes Robert R , Simpson Diane , Reeves Sally A. , Noble Robert C. , Thornsberry Clyde , Culver David , Allen James R. , Martone William J.
Published: August 2016

In the neonatal intensive care unit (NICU) of one hospital, 16 infants became colonized or infected with multiply-resistantEscherichia coli(MR-E.coli) over an 8-month period. Isolates were obtained from blood, urine, and sputum of three patients and from rectal surveillance cultures of 13 patients. The one patient with the blood isolate died. A matched case-control study identified continuous feeding (nine of 16 cases vs. one of 16 controls, p ≤ 0.001) and receipt of aminoglycosides (p ≤ 0.03) as risk factors. For case-babies not exposed to continuous feeding, duration of bolus feeding was significantly greater than for their controls (cases, 22 days; controls, 7 days; p ≤ 0.02). All 16 isolates were the same serotype and were resistant to amikacin, tobramycin, kanamycin, and gentamicin. The epidemiologic investigation suggested that MR-E. colimay have spread from person-to-person on the hands of personnel and that MR-E. colipersisted in the NICU for 8 months until effective control measures were instituted.
Bacteriological Sampling of Telephones and Other Hospital Staff Hand-Contact Objects
Authors: Rafferty Karen M. , Pancoast Stephen J.
Published: August 2016

In an acute-care general hospital, 114 telephones, intercoms, dictaphones, and bedpan flusher handles were sampled in patient-care areas for type of bacterial contamination. Nine of these (7%) demonstrated potentially pathogenic bacteria including Klebsiella, Enterobacter, Pseudomonas and Aeromonas. Inanimate, environmental, staff hand-contact objects were only lightly contaminated, did not represent a significant reservoir of gram-negative organisms, and therefore, would be unlikely to be a vehicle of transmission of gram-negative bacteria from the hands of one staff member to another under routine circumstances. Surveillance and disinfection of telephones and related hand-contact items in the hospital appear unnecessary.
Cost-Effectiveness of the Two-Step Skin Test for Tuberculosis Screening of Employees in a Community Hospital
Authors: Lé Chinh T.
Published: August 2016

To assess the frequency of the booster effect as well as the need for and the cost effectiveness of the two-step skin test for tuberculosis screening at our medical center, we conducted a pilot study from June 1980 to March 1983 with hospital and clinic employees. Six (0.4%) of 1,521 employees tested by the two-step skin test demonstrated the booster effect. The mean age of these six employees was 35 years (range, 24 to 44 yr). During the study period, 10 employees converted to a positive skin test. The booster effect would have accounted for approximately 38% (6 of 16) of those converting if the two-step testing were not performed. At our medical center, the additional cost of the two-step skin test was low and justifiable for medical and epidemiologic reasons. We suggest that each hospital review the prevalence of tuberculosis among its patient and employee populations. The need for and cost effectiveness of the two-step skin test for new hospital employees must be re-examined on the basis of these data.
Employee Work Restrictions for Infection Control
Authors: Valenti William M.
Published: August 2016

From time to time, health care workers are restricted from patient contact because of proven or suspected infectious illness or because of incubating disease after an exposure. The CDC Guideline for Infection Control in Hospital Personnel addresses a number of infectious illnesses and exposures which may require some type of employee restriction from patient contact. However, the Guideline does not address the administrative aspects that accompany putting an employee on a leave of absence for infection control purposes. This process is often complicated and questions frequently arise as to how an employee should be paid for the time lost from work. In general, there is no uniform way to approach the problem of “absence to prevent contagion.” As with many areas of infection control and employee health, hospitals can choose one of several options. However, the employee should never be penalized for reporting an infectious illness or exposure, and administrators should encourage reporting of proven or suspected disease or exposures (eg, exposure to chickenpox).
Bedside Resuscitation Bags: A Source of Bacterial Contamination
Authors: Thompson Anne C. , Wilder Barbara J. , Powner David J.
Published: August 2016

Resuscitation bags at the bedside of 12 intubated ICU patients with known culture positive sputum were evaluated as possible reservoirs of pathogenic bacteria. As oxygen was constantly flowing into the bags, sampling of gas continuously emitted from the exhalation valve assembly was sampled to detect if a bacteria-laden aerosol was being created. Positive cultures were obtained from 75% of the valves and 25% of the aerosol samples. In those patients with gram-negative bacteria in their sputum, 71% of the valves and 29% of the gas samples were positive for the same organisms. Various methods to control this possible contributing factor to nosocomial infection in the ICU are discussed.
Postoperative Wound Infections Following Cardiac Surgery: Significance of Contaminated Cases Performed in the Preceding 48 Hours
Authors: deSilva Malkanthie I. , Rissing J. Peter
Published: August 2016

Postoperative wound infections following open heart cardiac surgery increased markedly after hospital relocation (7 of 77v; 4 of 320; p = .0007). Of the multiple identified risk factors, significant patient and procedural association included prolonged operative time of infected patients (384 minutes ± 115 SDv318 ± 67, p = .025) and operation in a room used within the previous 48 hours for a contaminated case (4/7 infectedv10/67 not infected; p = .023). Several defects were discovered in the air handling system. After appropriate changes, the infection rate decreased in the next 12 months (1 of 109; p < .02). Other concurrent surgical wound infection rates remained unchanged suggesting that defective air handling may have impacted only on the open heart cardiac surgery patients. Preceding contaminated surgery and prolonged operative time were associated with postoperative wound infections in cardiac surgery.
Brief Report: Needle Punctures—Documentation and Incidence Rate Calculation
Authors: Fishman Marlene , Cathers Alan F. , Stamp Deborah
Published: August 2016

Potential hazards of puncture wounds have been well-defined and include transmission of hepatitis B virus, acquired immunodeficiency syndrome, syphilis, malaria, and other infectious diseases. Yet, standard methodology has not been used for statistical comparison. Attack rates have been expressed as needlesticks per full-time equivalents, needlesticks per employee per year, punctures per number of personnel, or punctures per number of hospital beds. These calculations do not account for the amount of time during which an employee is at risk of receiving a needle puncture. Also, numbers alone cannot account for intensity of care, potential exposures, or hours at risk. Nor can numbers provide an estimate of potential risk. A rate is more valuable than numbers because it measures the probability of occurrence. A meaningful incidence rate would be based on uniform data collection and would provide the number of puncture wounds per year for a standardized work period. This is similar in concept to nosocomial infections per patient-days of exposure. We propose the application of standard labor statistics methodology which accounts for man-hours worked, can be readily obtained in health care facilities, and can be modified as described here.
Neisseria meningitidis
Authors: Stephens David S.
Published: August 2016

Neisseria meningitidisis an exclusive human pathogen. The organism was first recognized by Weichselbaum in 1887 in the spinal fluid of six patients with acute cerebrospinal meningitis. He called itDiplococcus intracellularis meningitidisbecause of the presence of the organism within leukocytes from the spinal fluid. Subsequent studies established the meningococcus as the cause of epidemic cerebrospinal fever and placed the organism in the genusNeisseria. Despite the availability of effective antimicrobials and partially effective vaccines,N. meningitidisremains one of the most frequent causes of rapidly fatal sepsis and meningitis.
KlebsiellaMarker Systems
Authors: Rubin Sally Jo
Published: August 2016

Klebsiellamarker systems include determination of susceptibility patterns, serotype, bacteriocin susceptibility, bacteriophage susceptibility, biotype, and plasmid content, size and endonuclease fragment size. Susceptibility patterns are useful only if unusual patterns (ie, aminoglycoside resistance) occur. Serotypes are stable, reproducible markers. Over 90% of isolates can be serotyped and epidemiologically unrelated strains are widely distributed among the 72 standard types. Antisera are not available commercially except to types 1 to 6 and serotyping is expensive and time-consuming. Bacteriocin susceptibility typing is easier and cheaper but reproducibility is sometimes poor. Depending on the producer strains used, between 67% and 96% of strains are typable. As a single typing method, bacteriophage typing is not very sensitive. Only 70% of strains are typable and 20% are of a single type. There are two major problems with most biotyping systems: poor reproducibility and poor sensitivity. A high percent of strains is the same type. Plasmid analysis is technically the most complicated but is important if strains are aminoglycoside resistant. No one method is ideal, and characterization of isolates from an outbreak is best done by using several different marker systems.
The Epidemiology of Nosocomial Infections Caused byKlebsiella pneumoniae
Authors: Jarvis William R. , Munn Van P. , Highsmith Anita K. , Culver David H. , Hughes James M.
Published: August 2016

Klebsiella pneumoniaecauses serious epidemic and endemic nosocomial infections. We conducted a literature review to characterize the epidemiology of epidemicK. pneumoniaeoutbreaks. Eighty percent of the outbreaks (20/25) involved infections of the bloodstream or urinary tract. Person-to-person spread was the most common mode of transmission, and nearly 50% of the outbreaks occurred in neonatal intensive care units. No one serotype predominated, and no association was found between serotype and either the site of infection or the antimicrobial susceptibility pattern.

We used data reported to the Centers for Disease Control (CDC) by hospitals participating in the National Nosocomial Infections Study (NNIS) to describe the epidemiology of endemicK. pneumoniaeinfections. In die 8-year period from 1975 through 1982 the nosocomialK. pneumoniaeinfection rate was 16.7 infections per 10,000 patients discharged. The rate of infection at medical school-affiliated hospitals was significantly greater than at nonaffiliated hospitals; furthermore, the rate of infection at large affiliated hospitals was greater than at small affiliated hospitals. The rate of infection varied by service, with the highest rate found on the medicine service. During the 8-year period, 184 deaths were caused by nosocomialK. pneumoniaeinfections (184 deaths/16,969 infections, case-fatality ratio 1.1%), with higher ratios in pediatrics (5%) where there was a 12% mortality in children infected with an aminoglycoside-resistant strain.
Lack of Nosocomial Spread ofVaricellain a Pediatric Hospital with Negative Pressure Ventilated Patient Rooms
Authors: Anderson John D. , Bonner Mavis , Scheifele David W. , Schneider B. Christof
Published: August 2016

All patients at the new British Columbia's Children's Hospital with chickenpox orHerpes zosterare nursed with appropriate precautions in single-bed rooms provided with negative pressure ventilation. Over a period of 1 year, no nosocomial infections were detected on follow-up of 110 susceptible patients who had been on wards at the same time as six cases of chickenpox and one immunocompromised patient with cutaneous dissemination ofVaricella zoster. In a preceding study at the previous hospital, with similar staff, control measures, and patient population, in an isolation facility without negative pressure ventilation, nosocomial infections occurred in seven out of 41 susceptible patients who were on the same ward as two patients with chickenpox. These findings suggest that a simple negative pressure ventilation system without air locks is a useful adjunct in the control of cutaneousVaricellainfections.
Q Fever and Experimental Sheep
Authors:   International Council for Laboratory Animal Science, Grant Carl G. , Ascher Michael S. , Bernard Kenneth W. , Ruppanner Roger , Vellend Hillar
Published: August 2016

In August 1983 a Symposium was held in Vancouver to discuss Q fever as a hazard to humans in contact with infected sheep. On the basis of new preliminary information presented and discussion at the Symposium, an attempt has been made in this document to supplement published guidelines for the conduct of sheep research.
Isolation ofLegionella pneumophilafrom the Cold Water of Hospital Ice Machines: Implications for Origin and Transmission of the Organism
Authors: Stout Janet E. , Yu Victor L. , Muraca Paul
Published: August 2016

Although the mode of transmission ofL. pneumophilais as yet unclear, the hot water distribution system has been shown to be the reservoir for Legionella within the hospital environment. In this report we identify a previously unrecognized reservoir forL. pneumophilawithin the hospital environment, ie, the cold water dispensers of hospital ice machines. The cold water dispensers of 14 ice machines were cultured monthly over a 1-year period. Positive cultures were obtained from 8 of 14 dispensers, yielding from 1 to 300 CFU/plate. We were able to link the positivity of these cold water sites to the incoming cold water supply by recoveringL. pneumophilafrom the cold water storage tank, which is directly supplied by the incoming municipal water line. This was accomplished by a novel enrichment experiment designed to duplicate the conditions (temperature, sediment, stagnation, and continuous seeding) of the hot water system. Our data indicate that significant contamination of cold water outlets withL. pneumophilacan occur. Although no epidemiologic link to disease was made, the fact that the primary source of a patient's drinking water is from the ice machines warrants further investigation of these water sources as possible reservoirs.
Penicillins With Antipseudomonal Activity
Authors: Norris Sandra M.
Published: August 2016

The escalating role ofPseudomonas aeruginosaas a nosocomial pathogen, the relatively high mortality rate associated with pseudomonal infections, the intrinsic antibiotic resistance of this versatile, ubiquitous organism, and the growing number of reports of multiple antibiotic resistance developing during therapy ofPseudomonasinfections prompt a review of currently available penicillins with antipseudomonal activity. Ticarcillin, piperacillin, mezlocillin and azlocillin have upstaged carbenicillin, the first antipseudomonal, β-lactam agent clinically used, with other products “in the wings.”
Readerś Forum: Controlling Urges and Infections—Computer System Design for Epidemiology
Authors: Barr Richard L. , Gerzoff Robert B.
Published: August 2016

By now, most of us have seen IBM's version of Charlie Chaplin's tramp in their omnipresent advertising campaign: each commercial begins with the little tramp struggling valiantly to keep up with the complexity of modern business, only to find himself up to his neck in hats or, more recently, roller skates; of course the IBM personal computer soon arrives to save him by replacing cacophony and chaos with computational harmony and the soothing sounds of smooth skating. It is no accident that the little tramp was chosen to represent the harried everyman—Charlie Chaplin made the connection himself in his film Modern Times. There, as in the IBM campaign, he struggled valiantly but vainly to master the madness of modern mechanical times. IBM's message is clear: computers do not increase the madness, but cure it; the micro is the machine to tame the machine age.
Clinical Pharmacology of Antibiotics: Do Antibiotics Interfere with Host/Bacterial Interaction?
Authors: Shibl Atef M.
Published: August 2016

Antibiotics exert a number of effects on bacteria other than simply killing them or inhibiting their growth. Increasing evidence that exposure of bacteria to antibiotics induces profound alterations in the interaction between bacteria and host defense has been noted. The effect of antibiotics on polymorphonuclear leukocytes and the immune specific response of mononuclear cells is reviewed. An understanding of such effects would allow a more rational application of antibiotics, as well as provide direction in the development of new antibiotics that have both specific antibacterial action and positive effects on host defense mechanisms.
Readers:' Forum: Nosocomial Rubella—Consequences of an Outbreak and Efficacy of a Mandatory Immunization Program
Authors: Heseltine Peter N.R. , Ripper Marie , Wohlford Patricia
Published: August 2016

An outbreak of rubella in a large metropolitan hospital is described. Nineteen cases among employees and three secondary cases in family members occurred. Nosocomial cases occurred among the 3,900 employees of an adult medical-surgical unit where a voluntary program of rubella immunization was in effect. No cases occurred among the 1,400 employees of the women's and pediatric units with mandatory policies, despite interfacility and community exposure. Ten pregnant women were among the 377 contacts of the cases. Five were sero-negative to rubella. Two who developed clinical rubella, one asymptomatic sero-conversion and one other, all elected to terminate their pregnancies. The remaining woman, exposed in her third trimester delivered a normal infant. We conclude a policy requiring new employees to be rubella immune is more effective in preventing nosocomial rubella than a voluntary program and is desirable in view of the potential consequences of an outbreak to pregnant employees.
Cost Containment in Infection Control: Ethical Problems in Rationing Medical Care
Authors: Macklin Ruth
Published: August 2016

The era of cost containment is upon us. Bureaucrats and regulators, politicians and insurance administrators have begun to devise schemes for reducing the costs of hospital care and medical services in a country justly proud of the quality of its health care. The term “cost containment” has a neutral ring to it, a tone deliberately chosen by policy makers to soften the impact of its effects. The concept has an aura of virtue, conjuring an image of overflowing expenditures that must be put back into the container. But let us recognize the harsh reality that cost containment is simply another term for rationing, a notion that has somewhat unsavory connotations.

The need to embark on rationing arises when a crisis of available goods or services is imminent. We are told that too much money is being spent today on health care in the US. Since spending too much on anything is considered wasteful, and since wastefulness is at least an inefficient, if not an unethical way to treat resources, the conclusion seems inescapable that there is a moral imperative to cut costs in the health care sector. To be sure, the goals of eliminating waste and reducing excessive costs should be pursued by hospitals and physicians alike. But let us not hide behind these noble goals and accept uncritically the idea that to increase efficiency in delivering health care, it is necessary to embark on rationing schemes.
Characteristics ofPseudomonas aeruginosaIsolated From Whirlpools and Bathers
Authors: Highsmith Anita K. , Le Phuong Nhan , Khabbaz Rima F. , Munn Van P.
Published: August 2016

Pseudomonas aeruginosais the most frequently isolated microorganism from whirlpool water and lesions associated with outbreaks of dermatitis and folliculitis related to whirlpool exposure. Strains were selected from 19 outbreaks ofP. aeruginosainfections (1977 to 1983) associated with whirlpool use; they were examined to determine if the strains possessed unique virulence factors or characteristics that might aid in their selection in the environment.

P. aeruginosa, 011, was the predominant serotype isolated from whirlpool water as well as from bathers with dermatitis or folliculitis, followed by serotypes 09, 04, and 03. Antimicrobial susceptibility patterns were similar for all strains. Strains ofP. aeruginosafrom bathers and water demonstrated statistically significant differences in extracellular enzyme production compared with control strains.P. aeruginosa, serotypes 09 and 011, were found to be sensitive to low levels of chlorine. These data suggest that, if adequate levels of free available chlorine are maintained,P. aeruginosashould have little opportunity to persist in whirlpools.

A bather's risk ofP. aeruginosadermatitis or folliculitis appears to be affected primarily by three factors: 1) immersion in water colonized byP. aeruginosa, 2) skin hydration with altered skin flora, and 3) toxic reactions to extracellular enzyme or exotoxins produced byP. aeruginosa. Although a single virulence factor was not identified from the results of this study, there are some indications that the enzymes produced by these microorganisms play an important role in the pathogenesis of disease associated with whirlpool use.
Epidemiology and Clinical Significance of Blood Cultures Positive for Coagulase-Negative Staphylococcus
Authors: Kirchhoff Louis V. , Sheagren John N.
Published: August 2016

Coagulase-negative staphylococci are frequently isolated from blood cultures. As these organisms may occasionally cause serious disease, differentiating bacteremia from contamination is very important but often difficult. Over a 26-month period, of 29,542 blood cultures processed at the University of Michigan Medical Center, 2,875 (9.7%) were positive, and of those, 694 (from 527 patients) grew coagulase-negative staphylococci. Isolates from the 439 patients with only one blood culture positive for coagulase-negative staphy-lococci and those from the 18 patients with two positive cultures 10 days or more apart were deemed contaminants. Review of the records of the remaining 70 patients with multiple isolates indicated that 33 had had an episode of true bacteremia, 29 (87.9%) of which were associated with intravascular catheters or prosthetic valves. Overall, 85% of all coagulase-negative staphylococci isolated during the study period were judged to be contaminants. Seventy-one percent of the blood cultures drawn during the episodes of bacteremia were positive for coagulase-negative staphylococci as opposed to only 34% in the patients with contaminated cultures (p < 0.01). Moreover, coagulase-negative staphylococci grew in both aerobic and anaerobic bottles in 85% of blood culture sets drawn during episodes of bacteremia, but in only 30% of the cultures thought to be contaminated (p < 0.001). Growth of coagulase-negative staphylococci in less than 48 hours was also significantly associated with bacteremia (p < 0.01). Antibiotic sensitivity patterns were not useful in differentiating bacteremia from contamination. Thus, clinicians should consider coagulase-negative staphylococci as true blood pathogens in patients with intravascular devices who have a high proportion of blood cultures positive for this organism over a short period of time, and whose cultures became positive in less than 48 hours, with a high percent positive in both bottles. Microbiology laboratories can conserve considerable resources by limiting sensitivity studies to isolates from such patients.
Immunity of Hospital Personnel Against Polio Virus
Authors: Alkan M. , Morag R. , Rubinstein E. , Derazne E.
Published: August 2016

Sera from 275 employees of three hospitals were tested for the presence of antibodies to polio virus. Immunity was found to increase with age, and was higher in personnel directly involved in patient care than in the others. Previous exposure to poliomyelitis as well as a history of previous immunization did not correlate with the immunological status of the employee. When antibodies against one of the three polio types or more could not be demonstrated, the employee was vaccinated by an inactivated polio virus vaccine.
All-inclusive Concurrent Antibiotic Usage Review: A Way to Reduce Misuse Without Formal Controls
Authors: Heineman Herbert S. , Watt Valerie S.
Published: August 2016

During an 11-week period, all antibiotic usage on a 113-bed medical teaching service was reviewed concurrently in weekly sessions between house staff and a review team. Recommendations for change, based on accepted criteria, were communicated by the house officer to the attending physician. In one-half of the patients no change was suggested; in one-third, a recommended change was made; and in only one-sixth was a recommendation not followed. Cost savings were conservatively estimated to approach $10,000 in this pilot study; this extrapolates to almost $300,000 per year for the 714-bed medical center, or more than 18% of the antibiotic expenditures.

This program achieves its objective in a nonthreatening, noncontrolling manner, provides continuing education, and contributes to improved patient care.
The Efficacy of a Florida Hospital Consortium for Infection Control: 1975-1982
Authors: Ehrenkranz N. Joel
Published: August 2016

From 1975 through 1982, the South Florida Hospital Consortium for Infection Control provided consultative and educational services to personnel of 20 community hospitals. To evaluate program efficacy, outbreak frequencies were compared at 11 hospitals with 5 to 8 years of experience through 1982. Annual outbreak rates during the first 4 membership years were compared with those of subsequent years, by service. Each hospital served as its own control. Outbreaks were most frequent in critical care and orthopedic-general surgery patients, and among hospital personnel. Critical care outbreaks occurred more often in hospitals classified as oncology centers (P<.05); their frequency did not decrease significantly after 4 years of membership. However, surgical outbreak rates did decrease from .36 annually in the first years to .03 thereafter (P<.01). This was not attributable to a secular decrease and is taken to indicate program efficacy. No change in frequency of hospital personnel outbreaks was evident.
Readers' Forum Results of a Survey of Infection Control Practices for Respiratory Therapy Equipment
Authors: Goularte Theresa A. , Craven Donald E.
Published: August 2016

The responses to a comprehensive survey of infection control practices for respiratory therapy equipment, previously published in the Readers' Forum section of Infection Control, are summarized in Tables 1 through 3. Responses were obtained from 205 United States hospitals; 65% were community hospitals and 38% had <500 ventilator days/year. In some cases, the total number of responses exceeded 100% because of practices that required multiple responses.
Gentamicin-Resistance Plasmids in an Intensive Care Unit
Authors: Shlaes David M. , Currie-McCumber Charlotte , Eanes Mabel , Rotter Grace , Floyd Rachel
Published: August 2016

To better understand the role of plasmids and their importance in the endemic antibiotic resistance of Enterobacteriaceae, we began a prospective study of our combined medical intensive care/coronary care unit. An initial culture survey of the patients, ward staff, and environment was followed by a prospective sampling of 139 consecutive new admissions at the time of admission to the unit, and at regular intervals thereafter for the remainder of their stay. All cultures were planted on agar-containing gentamicin. Of the 147 patients studied, 12 (8.2%) were colonized with 20 strains of gentamicin-resistant gram-negative bacilli (GRGNB) at 29 sites. An additional four GRGNB were isolated from the environment. Of the 24 GRGNB strains, 7 (29%) Enterobacteriaceae carried plasmids shown to carry the gentamicin-resistance determinant. Plasmids were further characterized by restriction endonuclease digestion profiles of plasmid DNA purified fromE. coliC600 transconjugants or transformants. A 93 kb plasmid introduced to the unit by aSerratia liquefacienscolonizing a patient transferred from another area in the hospital was identical to 93 kb plasmids carried by aC. amalonaticusand anE. aerogenessubsequently colonizing another patient on the unit. A 60 kb plasmid, first isolated from aS. marcescenscolonizing a sink drain was later isolated from anE. cloacaecolonizing a patient. Our results indicate that spread of specific R-plasmids may be one mechanism for dissemination of antibiotic resistance on our MICU/CCU.
Viability of Staphylococci in Various Diluents
Authors: Essiain Razmick , Flournoy D.J
Published: August 2016

Standardized suspensions of 78 staphylococci and micrococci were stored in different diluents and tested periodically for 3 weeks to determine their ability to maintain viability. In 92% of the tests, diluent suspensions yielded viable organisms for at least 21 days. Organism survival was maintained in the following order, from best to worst: skim milk, tap water, 0.9% NaCl, deionized water, Dianeal (peritoneal dialysis) fluid, 0.2% bovine serum albumin and 5% glycerol. In 81% of the instances, oxacillin-susceptible staphylococci survived better than oxacillin-resistant staphylococci.
Adapting Disease-Specific Isolation Guidelines to a Hospital Information System
Authors: Jacobson Julie T. , Johnson Dickey S. , Ross Carol A. , Conti Marlyn T. , Evans R. Scott , Burke John R
Published: August 2016

The authors modified the Centers for Disease Control's guideline for disease-specific isolation precautions to a hospital computerized information system. Entering a suspected diagnosis selected from the isolation option on computer terminals generated: 1) a printout listing the isolation instructions, infective material(s), and persons who should avoid exposure; 2) an order for the appropriate supplies; 3) a patient charge based on the supplies required; and 4) an option for stopping, changing, or listing the orders. In order to implement this system, both extensive in-service training for nurses and efforts to change ordering practices of physicians were necessary.

Prevalence surveys before and after computerization were used to evaluate the new system. Combined surveys showed that isolation was ordered for only 21% of patients when indicated. Failure to isolate was identified as a significant problem. As a consequence, continuous surveillance and consultation of all infected patients were instituted, resulting in isolation orders for 81% when indicated. The computerized disease-specific system has resulted in better and more accurate use of isolation, probably due to in service education and surveillance efforts.
Biological Sterilization Monitors: A Four-Year In-Use Evaluation of Two Systems
Authors: Kotilainen Helen Rosen , Gantz Nelson M.
Published: August 2016

Biological monitors (BI) are considered to be the best monitor of the sterilization process yet false positives may result in recalls and quality assurance difficulties. To assess the frequency, type and reasons for questionable results, we undertook a 4-year in-use study of two commonly used BI types—spore strips (Spordi®) and a self-contained crushable ampule (Attest®)—for both steam and ethylene oxide (EO). After laboratory verification of time/kill ratios for a portion of each involved lot, 2 BI of each type were placed in test pack within a randomly selected load run at standard time and temperature. All resulting positive BI were subcultured. Steam cycle positives were uncommon (32/1,1710 positive Spordi, 1.9%; 20/1,710 positive Attest, 1.2%) and could be related to chamber temperature or steam quality. All of the 4 BI per load were positive in only three loads; physical monitors indicated gross malfunction. Five positive Spordi were due to either contaminants or a malfunctioning incubator. EO-related positives were more common (53/1,109 positive Spordi, 4.8%; 25/1,109 positive Attest, 2.3%). One-half of the Spordi tests became positive after 48 hours of incubation. Organisms other thanB. subtiliswere recovered from 49.1% of the positive tests (26/53). The Attest was remarkable for its lack of contamination; 1/25 was positive forPseudomonas stutzerionly. More positives were observed during the winter months when relative humidity was below 20%. This finding was more commonly observed with the EO Attest. In summary, we found no significant difference in the performance of either BI. Subculturing of positives and maintenance of proper humidity during storage should be emphasized.