bluuebunny/crossref_metadata_2025 huggingface dataset:
Diffuse Intralobular Liver Fibrosis in Dogs Naturally Infected with Leishmania (Leishmania) chagasi
Authors: Melo Ferdinan , Amaral Marina , Oliveira Patricia , Lima Wanderson , Andrade Marina , Michalick Marilene , Raso Pedro , Tafuri Washington , Tafuri Wagner
Published: September 2018

The aim of this study was to evaluate the diffuse intralobular fibrosis in dogs naturally infected with Leishmania (Leishmania) chagasi. One hundred five infected animals with positive serologic tests for Leishmania were divided into two clinical groups: 69 symptomatic animals and 36 asymptomatic. Special staining with Gomori, Heidenhain, Silver, and Picrosirius Red was applied to characterize fibrilopoesis. The tissue parasite load was measured by immunohistochemistry and associated histomorphometric analyses. Intralobular fibrosis was observed in all dogs, and more collagen deposition was confirmed in the infected animals than in the controls by these histomorphometric studies. There were significant differences among the distinct clinical groups. In fact, symptomatic dogs showed an increased collagen deposition in the liver compared with asymptomatic ones. A peculiar diffuse intralobular fibrosis, where the collagen fibers encircled small groups of hepatocyte(s), was observed in two cases (1.9%).
Prevalent Genotypes of Toxoplasma gondii in Pregnant Women and Patients from Crete and Cyprus
Authors: Messaritakis Ippokratis , Detsika Maria , Koliou Maria , Sifakis Stavros , Antoniou Maria
Published: September 2018

Molecular genotyping has been used to characterize Toxoplasma gondii strains into the three clonal lineages known as types I, II, and III. To characterize T. gondii strains from Greece and Cyprus, polymerase chain reaction–restriction fragment length polymorphism analysis on the GRA6 gene was performed directly on 20 clinical samples from 18 humans (11 pregnant women, six patients with lymphadenopathy, and one patient positive for human immunodeficiency virus) and two rats. Characterization of T. gondii types was performed after digestion of amplified products with Mse I. The 20 strains were characterized as type II (20%) and type III (80%). Of these strains, 19 originated from the island of Crete (4 strains type II and 15 strains type III), and 1 from the island of Cyprus (type III). Although both type II and type III strains were found, type III was the most prevalent in Crete.
Epidemiology of Cryptosporidiosis in North American Travelers to Mexico
Authors: Nair Parvathy , Mohamed Jamal A. , DuPont Herbert L. , Figueroa Jose Flores , Carlin Lily G. , Jiang Zhi-Dong , Belkind-Gerson Jaime , Martinez-Sandoval Francisco G. , Okhuysen Pablo C.
Published: September 2018

We studied 1,179 North American travelers who visited Mexico from 2005 to 2007. Travelers’ diarrhea (TD) was reported by 521 (44%) participants. Among subjects with TD, 218 cases were examined for cryptosporidiosis by polymerase chain reaction (PCR) and enzyme-linked immunoassays (ELISA). There were 14 (6%) cases of cryptosporidiosis and 141 cases (64%) of bacterial diarrhea. Compared with bacterial diarrhea, a longer stay in Mexico was a risk factor for cryptosporidiosis. Additionally, Cryptosporidium cases passed greater number of watery stools (P < 0.05), suffered more episodes of diarrhea (P ≤ 0.05), and were more likely to experience tenesmus (P ≤ 0.05) compared with bacterial causes of TD. ELISA detected seven (3%) cases of Cryptosporidium, whereas PCR identified an additional seven cases (6%). Speciation by 18SrRNA sequencing showed that 13 cases were caused by C. parvum and only 1 case was caused by C. hominis. ELISA showed a sensitivity of 50% and specificity of 100% compared with PCR.
Spatial and Temporal Patterns in Pupal and Adult Production of the Dengue Vector Aedes aegypti in Kamphaeng Phet, Thailand
Authors: Koenraadt Constantianus J. M. , Aldstadt Jared , Kijchalao Udom , Sithiprasasna Ratana , Getis Arthur , Jones James W. , Scott Thomas W.
Published: September 2018

We investigated how temporal and spatial effects confound the functional relationship between pupal and adult populations of Aedes aegypti and thus the value of pupal numbers as predictors of dengue transmission risk in Kamphaeng Phet, Thailand. We found considerable seasonal shifts in productivity of key containers. Tires contained much less pupae in the dry season than in the wet season. Earthenware jars and cement tanks for washing purposes were consistent producers over the entire study period. Houses in the two villages, with approximately twice as many houses per unit area, were significantly more likely to have adults and pupae. No significant annual, seasonal, or spatial effects on the strength of correlations between pupal and adult populations were found. Except for 2 (of 16) occasions, pupal, and adult populations were correlated strongly in time and space. Our results are consistent with application of the pupal survey technique for assessing dengue transmission risk.
Rapid Suppression of Onchocerca volvulus Transmission in Two Communities of the Southern Chiapas Focus, Mexico, Achieved by Quarterly Treatments with Mectizan
Authors: Rodríguez-Pérez Mario A. , Lutzow-Steiner Miguel A. , Segura-Cabrera Aldo , Lizarazo-Ortega Cristian , Domínguez-Vázquez Alfredo , Sauerbrey Mauricio , Richards Frank , Unnasch Thomas R. , Hassan Hassan K. , Hernández-Hernández Raymundo
Published: September 2018

The impact of quarterly Mectizan (ivermectin) treatments on transmission, microfiladermia, and ocular lesions was evaluated in two formerly hyperendemic communities (Las Golondrinas and Las Nubes II) located in the main endemic focus for onchocerciasis in Southern Chiapas, Mexico. The data suggest that Onchocerca volvulus transmission has been suppressed after elimination of microfiladermia in these two communities. Increasing the frequency of Mectizan treatment to four times per year appears to have resulted in the rapid suppression of transmission in communities with residual transmission.
Does Cotrimoxazole Prophylaxis for the Prevention of HIV-Associated Opportunistic Infections Select for Resistant Pathogens in Kenyan Adults?
Authors: Hamel Mary J. , Greene Carolyn , Chiller Tom , Ouma Peter , Polyak Christina , Otieno Kephas , Williamson John , Shi Ya Ping , Feikin Daniel R. , Marston Barbara , Brooks John T. , Poe Amanda , Zhou Zhiyong , Ochieng Benjamin , Mintz Eric , Slutsker Laurence
Published: September 2018

We assessed the effect of daily cotrimoxazole, essential for HIV care, on development of antifolate-resistant Plasmodium falciparum, naso-pharyngeal Streptococcus pneumoniae (pneumococcus), and commensal Escherichia coli. HIV-positive subjects with CD4 cell count < 350 cells/μL (lower-CD4; N = 692) received cotrimoxazole; HIV-positive with CD4 cell count ≥ 350 cells/μL (higher-CD4; N = 336) and HIV-negative subjects (N = 132) received multivitamins. Specimens were collected at baseline, 2 weeks, monthly, and at sick visits during 6 months of follow-up to compare changes in resistance, with higher-CD4 as referent. P. falciparum parasitemia incidence density was 16 and 156/100 person-years in lower-CD4 and higher-CD4, respectively (adjusted rate ratio [ARR] = 0.11; 95% confidence interval [CI] = 0.06–0.15; P < 0.001) and 97/100 person-years in HIV-negative subjects (ARR = 0.62; 95% CI = 0.44–0.86; P = 005). Incidence density of triple and quintuple dihydrofolate-reductase/dihydropteroate-synthetase mutations was 90% reduced in lower-CD4 compared with referent. Overall, cotrimoxazole non-susceptibility was high among isolated pneumococcus (92%) and E. coli (76%) and increased significantly in lower-CD4 subjects by Week 2 (P < 0.005). Daily cotrimoxazole prevented malaria and reduced incidence of antifolate-resistant P. falciparum but contributed to increased pneumococcus and commensal Escherichia coli resistance.
Two Clustering Diffusion Patterns Identified from the 2001–2003 Dengue Epidemic, Kaohsiung, Taiwan
Authors: Kan Chih-Chun , Lee Pei-Fen , Wen Tzai-Hung , Chao Day-Yu , Wu Min-Huei , Lin Neal H. , Huang Scott Yan-Jang , Shang Chuin-Shee , Fan I-Chun , Shu Pei-Yun , Huang Jyh-Hsiung , King Chwan-Chuen , Pai Lu
Published: September 2018

This study analyzed the spatio-temporal patterns of 4,587 (94% of the total) confirmed dengue cases in Kaohsiung and Fengshan Cities (a two-city area) that occurred in Taiwan from 2001 to 2003. The epidemic had two simultaneous distinct diffusion patterns. One was a contiguous pattern, mostly limited to 1 km from an initial cluster, reflecting that there was a rapid dispersal of infected Aedes aegypti and viremic persons. The second followed a relocation pattern, involving clusters of cases that diffused over 10 weeks starting from the southern and moving to the northern parts of the two-city area. The virus from one clustering site jumped to several distant areas where it rapidly dispersed through a series of human–mosquito transmission cycles to several localities. In both patterns, transmission of disease quickly enlarged the epidemic areas. Future dengue control efforts would benefit from a timely syndromic surveillance system plus extensive public education on how to avoid further transmission.
Desialylation of Plasma Proteins in Severe Dengue Infection: Possible Role of Oxidative Stress
Authors: Rajendiran Soundravally , Lakshamanappa Hoti Sugeerappa , Zachariah Bobby , Nambiar Selvaraj
Published: September 2018

Oxidative stress in dengue infection has been suggested. This study was carried out to explore the plasma protein oxidation and its sialic acid content in dengue infection. Thirty-two dengue hemorrhagic fever (DHF), 25 dengue shock syndrome (DSS), 29 dengue fever (DF), and 63 healthy controls were included in this study. The extent of carbonylation, sulphydryl content, and desialylation of plasma protein was estimated in acute phase sample. Significantly higher levels of protein carbonyls and lower levels of sialic acid and sulphydryl groups were found in DHF and DSS compared with DF using one-way analysis of variance. Regression analysis showed that desialylation is dependent on protein carbonyls in DHF/DSS. This study indicates that, in dengue infection, plasma proteins undergo increased levels of desialylation, which can be attributed to the oxidative stress. Future studies on sialylation status of endothelium and platelets can show light into the pathogenesis of the dengue infection.
Challenges in Routine Implementation and Quality Control of Rapid Diagnostic Tests for Malaria–Rufiji District, Tanzania
Authors: McMorrow Meredith L. , Masanja M. Irene , Abdulla Salim M. K. , Kahigwa Elizeus , Kachur S. Patrick
Published: September 2018

Rapid diagnostic tests (RDTs) represent an alternative to microscopy for malaria diagnosis and have shown high sensitivity and specificity in a variety of study settings. Current World Health Organization (WHO) guidelines for quality control of RDTs provide detailed instructions on pre-field testing, but offer little guidance for quality assurance once RDTs are deployed in health facilities. From September 2006 to April 2007, we introduced a histidine-rich protein II (HRP2)-based RDT (Paracheck) for suspected malaria cases five years of age and older in nine health facilities in Rufiji District, Tanzania, to assess sensitivity and specificity of RDTs in routine use at rural health facilities. Thick blood smears were collected for all patients tested with RDTs and stained and read by laboratory personnel in each facility. Thick smears were subsequently reviewed by a reference microscopist to determine RDT sensitivity and specificity. In all nine health facilities, there were significant problems with the quality of staining and microscopy. Sensitivity and specificity of RDTs were difficult to assess given the poor quality of routine blood smear staining. Mean operational sensitivity of RDTs based on reference microscopy was 64.8%, but varied greatly by health facility, range 18.8–85.9%. Sensitivity of RDTs increased with increasing parasite density. Specificity remained high at 87.8% despite relatively poor slide quality. Institution of quality control of RDTs based on poor quality blood smear staining may impede reliable measurement of sensitivity and specificity and undermine confidence in the new diagnostic. There is an urgent need for the development of alternative quality control procedures for rapid diagnostic tests that can be performed at the facility level.
Spatial Analysis of Risk Factor of Cholera Outbreak for 2003–2004 in a Peri-urban Area of Lusaka, Zambia
Authors: Sasaki Satoshi , Suzuki Hiroshi , Igarashi Kumiko , Tambatamba Bushimbwa , Mulenga Philip
Published: September 2018

A cholera outbreak occurred in Lusaka city between November 28, 2003 and June 8, 2004, and 6,542 cases with 187 deaths (case fatality rata: 2.86) were reported. We analyzed the distribution of cholera cases, the mode of cholera transmission, and the risk factors affecting cholera infection in a peri-urban area of Lusaka by using a Geographic Information System (GIS) and a matched case-control method. Chloropleth mapping of the incidences of cholera showed variation of the incidences in the study area. Our analysis indicated a significant association between the lack of latrine and drainage systems surrounding houses and high incidence of cholera. The matched case-control study showed the protective role of chlorination of drinking water and of hand washing with soap for cholera prevention. We concluded that cholera occurred because of personal behavior and the environment conditions of daily life.
Natural Infection of Lutzomyia tortura with Leishmania (Viannia) naiffi in an Amazonian Area of Ecuador
Authors: Kato Hirotomo , Gomez Eduardo A. , Yamamoto Yu-ichi , Calvopiña Manuel , Guevara Angel G. , Marco Jorge D. , Barroso Paola A. , Iwata Hiroyuki , Hashiguchi Yoshihisa
Published: September 2018

Natural infection of sand flies with Leishmania parasites was surveyed in an Amazonian area in Ecuador where leishmaniasis is endemic. Seventy-one female sand flies were dissected and one was positive for Leishmania protozoa. The species of this sand fly was identified as Lutzomyia (Lu.) tortura on the basis of morphologic characteristics. Analysis of the cytochrome b gene sequence identified the parasite as L. (Viannia) naiffi. We report the distribution of L. (V.) naiffi in Ecuador and detection of a naturally infected sand fly in the Ecuadorian Amazon and natural infection of Lu. tortura with Leishmania parasites in the New World.
Experimental Infection of Eastern Gray Squirrels (Sciurus carolinensis) with West Nile Virus
Authors: Gómez Andrés , Kramer Laura D. , Dupuis Alan P. , Kilpatrick A. Marm , Davis Lauren J. , Jones Matthew J. , Daszak Peter , Aguirre A. Alonso
Published: September 2018

Eastern gray squirrels (Sciurus carolinensis) have shown high West Nile virus (WNV) seroprevalence, and WNV infection has been suggested as a cause of morbidity and mortality in this species. We experimentally infected nine eastern gray squirrels with WNV to determine the clinical effects of infection and to assess their potential role as amplifying hosts. We observed no morbidity or mortality attributable to WNV infection, but lesions were apparent in several organs. We detected mean viremias of 105.1 and 104.8 plaque-forming units (PFU)/mL on days 3 and 4 post-infection (DPI) and estimated that ~2.1% of Culex pipiens feeding on squirrels during 1–5 DPI would become infectious. Thus, S. carolinensis are unlikely to be important amplifying hosts and may instead dampen the intensity of transmission in most host communities. The low viremias and lack of mortality observed in S. carolinensis suggest that they may be useful as sentinels of spillover from the enzootic amplification cycle.
National Malaria Control and Scaling Up for Impact: The Zambia Experience through 2006
Authors: Steketee Richard W. , Sipilanyambe Naawa , Chimumbwa John , Banda James J. , Mohamed Abdirahman , Miller John , Basu Suprotik , Miti Simon K. , Campbell Carlos C.
Published: September 2018

With its 2006–2011 National Malaria Strategic Plan, Zambia committed to control malaria at a national scale. This scale-up for impact approach was facilitated by sound business planning and financing in 2006 of approximately US$35 million. Compared with surveys in 2001 and 2004, a 2006 national survey of 14,681 persons in 2,999 households at the end of the transmission season showed substantial coverage increases for preventive interventions. Ownership and use rates of insecticide-treated mosquito nets (ITNs) among vulnerable groups doubled, with 44% of households owning ITNs and 23% of children less than five years of age and 24% of pregnant women using them. Roll Back Malaria Abuja targets for intermittent preventive treatment in pregnancy (IPTp) were exceeded, with 62% of pregnant women receiving at least two doses of IPTp. As of 2006, Zambia is demonstrating substantial progress toward the national targets (80% population coverage rates for the interventions) and aspires to show that malaria need not be its leading health problem, and that malaria control is a sound national investment.
Five-year Experience with Type 1 and Type 2 Reactions in Hansen Disease at a US Travel Clinic
Authors: Jacob Jesse T. , Kozarsky Phyllis , Dismukes Roberta , Bynoe Vicki , Margoles Lindsay , Leonard Michael , Tellez Ildefonso , Franco-Paredes Carlos
Published: September 2018

Very few data have been reported on the epidemiology and clinical features of leprosy reactions in non-endemic settings. We performed a retrospective descriptive analysis to define the frequency and features of Type 1 and Type 2 leprosy reactions in a cohort of patients followed at a US travel and tropical medicine clinic in a 5-year period. We identified that leprosy reactions presented in 10/14 (71.4%) patients with leprosy seen at our clinic. We identified that leprosy reactions occur frequently among patients living in non-endemic areas and may occur before the initiation of multi-drug therapy (MDT), during MDT, or even years after completion of therapy and may produce significant neurologic sequelae. This group of patients needs long-term clinical monitoring even after completion of MDT because of the need to continue either anti-inflammatory therapy, presence of severe neurologic sequelae after reactions, or the potential occurrence of late leprosy reactions.
Risk Factors for Dengue Virus Infection in Rural Amazonia: Population-based Cross-sectional Surveys
Authors: da Silva-Nunes Mônica , de Souza Vanda A. F. , Pannuti Cláudio S. , Sperança Márcia A. , Terzian Ana Carolina B. , Nogueira Maurício L. , Yamamura Anna M. Y. , Freire Marcos S. , da Silva Natal S. , Malafronte Rosely S. , Muniz Pascoal T. , Vasconcelos Helena B. , da Silva Eliana V. P. , Vasconcelos Pedro F. C. , Ferreira Marcelo U.
Published: September 2018

A comparison of dengue virus (DENV) antibody levels in paired serum samples collected from predominantly DENV-naive residents in an agricultural settlement in Brazilian Amazonia (baseline seroprevalence, 18.3%) showed a seroconversion rate of 3.67 episodes/100 person-years at risk during 12 months of follow-up. Multivariate analysis identified male sex, poverty, and migration from extra-Amazonian states as significant predictors of baseline DENV seropositivity, whereas male sex, a history of clinical diagnosis of dengue fever, and travel to an urban area predicted subsequent seroconversion. The laboratory surveillance of acute febrile illnesses implemented at the study site and in a nearby town between 2004 and 2006 confirmed 11 DENV infections among 102 episodes studied with DENV IgM detection, reverse transcriptase-polymerase chain reaction, and virus isolation; DENV-3 was isolated. Because DENV exposure is associated with migration or travel, personal protection measures when visiting high-risk urban areas may reduce the incidence of DENV infection in this rural population.
Evolution of Dengue Virus Type 2 during Two Consecutive Outbreaks with an Increase in Severity in Southern Taiwan in 2001–2002
Authors: Chen Hui-Ling , Lin Su-Ru , Liu Hsin-Fu , King Chwan-Chuen , Hsieh Szu-Chia , Wang Wei-Kung
Published: September 2018

To investigate viral determinants and evolution linked to outbreak with increased severity, we examined dengue virus type 2 (DENV-2) sequences from plasma of 31 patients (14 dengue fever, 17 dengue hemorrhagic fever, DHF) continuously during the 2001 and 2002 outbreaks in southern Taiwan, in which both the total cases and proportion of DHF cases increased. Analysis of envelope (E) and full-genome sequences between viruses of the two outbreaks revealed 5 nucleotide changes in E, NS1, NS4A, and NS5 genes. None was identical to those reported in the DENV-2 outbreak in Cuba in 1997, suggesting viral determinants linked to severe outbreak are genotype dependent. Compared with previous reports of lineage turnover years apart, our findings that the 2002 viruses descended from a minor variant of the 2001 viruses in less than 6 months was novel, and may represent a mechanism of evolution of DENV from one outbreak to another.
A Dry-format Field-deployable Quantitative Reverse Transcriptase-polymerase Chain Reaction Assay for Diagnosis of Dengue Infections
Authors: Wu Shuenn-Jue , Pal Subhamoy , Ekanayake Sajeewane , Greenwald David , Lara Silvia , Raviprakash Kanakatte , Kochel Tadeusz , Porter Kevin , Hayes Curtis , Nelson William , Callahan Johnny
Published: September 2018

We have systematically evaluated a dry-format, quantitative reverse transcriptase-polymerase chain reaction (qRT-PCR) assay developed by Tetracore Inc. for the Cepheid SmartCycler platform to facilitate rapid diagnosis of dengue virus infections. A panel of related flaviviruses was used to evaluate the clinical specificity of the assay, and it was found to be specific to dengue. Eighty-one clinical samples previously confirmed dengue positive by virus isolation, along with 25 dengue negative control specimens were used to validate this new diagnostic assay. Using these clinical samples, the assay exhibited 98.77% sensitivity and 100% specificity. Over 85% of the clinical specimen exhibited viral loads ranging from 103 to 107 plaque-forming units per milliliter (PFU/mL). In addition, this dry-format assay is stable at ambient temperatures and requires minimal technical expertise to perform in a small thermocycler platform. These characteristics make it a promising candidate for diagnosis of dengue in mobile laboratories in the field.
Impregnated Netting Slows Infestation by Triatoma infestans
Authors: Levy Michael Z. , Quíspe-Machaca Victor R. , Ylla-Velasquez Jose L. , Waller Lance A. , Richards Jean M. , Rath Bruno , Borrini-Mayori Katty , del Carpio Juan G. Cornejo , Cordova-Benzaquen Eleazar , McKenzie F. Ellis , Wirtz Robert A. , Maguire James H. , Gilman Robert H. , Bern Caryn
Published: September 2018

We used sentinel animal enclosures to measure the rate of infestation by the Chagas disease vector, Triatoma infestans, in an urban community of Arequipa, Peru, and to evaluate the effect of deltamethrin-impregnated netting on that rate. Impregnated netting decreased the rate of infestation of sentinel enclosures (rate ratio, 0.23; 95% confidence interval, 0.13–0.38; P < 0.001), controlling for the density of surrounding vector populations and the distance of these to the sentinel enclosures. Most migrant insects were early-stage nymphs, which are less likely to carry the parasitic agent of Chagas disease, Trypanosoma cruzi. Spread of the vector in the city therefore likely precedes spread of the parasite. Netting was particularly effective against adult insects and late-stage nymphs; taking into account population structure, netting decreased the reproductive value of migrant populations from 443.6 to 40.5. Impregnated netting can slow the spread of T. infestans and is a potentially valuable tool in the control of Chagas disease.
Glucose Kinetics during Fasting in Young Children with Severe and Non-severe Malaria in Suriname
Authors: Zijlmans Wilco , van Kempen Anne , Ackermans Mariëtte , de Metz Jesse , Kager Piet , Sauerwein Hans
Published: September 2018

Fasting could be an important factor in the induction of hypoglycemia in children with malaria because fasting results in a decrease in endogenous glucose production. The influence of extended fasting on plasma glucose concentration, glucose production, and gluconeogenesis were measured using [6,6-2H2]glucose and 2H2O in 12 Surinamese children with severe malaria and compared with 16 children with non-severe malaria during a 16-hour controlled fast. Glucose concentration and glucose production were comparable after 8 hours of fasting and decreased in both groups (P < 0.001) with an extension of the fast up to 16 hours. Glucose concentration decreased faster in the non-severe group than in the severe group (P = 0.029). The decrease in glucose production was not different between groups (P = 0.954). Thus, fasting predisposes for hypoglycemia in young children with Plasmodium falciparum malaria. Hypoglycemia caused by fasting develops later in young children with severe malaria than in children with non-severe malaria.
Serum Levels of Cytokines in Two Ethnic Groups with Dengue Virus Infection
Authors: Restrepo Berta N. , Ramirez Ruth E. , Arboleda Margarita , Alvarez Gonzalo , Ospina Marta , Diaz Francisco J.
Published: September 2018

This study compared the serum levels of tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), and interferon gamma (IFN-γ) in 78 Colombian patients, from two ethnic groups, with dengue virus infection. TNF-α levels were significantly higher in Afro-Colombians than in Mestizos and IL-6 levels were significantly higher in Mestizos than in Afro-Colombians, during the acute phase. IFN-γ levels were similar in both ethnic groups. Significantly higher TNF-α levels were found in Afro-Colombians than in Mestizos in both dengue fever (DF) and dengue hemorrhagic fever (DHF). The IL-6 levels were higher in Mestizos than in Afro-Colombians among patients with DF, but levels of this cytokine were higher in Afro-Colombians than in Mestizos among patients with DHF. Levels of IFN-γ were higher in patients with DHF than DF. Higher levels of these cytokines were observed in secondary infection. These results suggest that ethnicity may contribute to differences in immune responses to dengue infections.
First Molecular Identification of Entamoeba moshkovskii in Human Stool Samples in Tunisia
Authors: Ayed Soumaya Ben , Aoun Karim , Maamouri Nadia , Abdallah Rym Ben , Bouratbine Aïda
Published: September 2018

We report the first intestinal infections in Tunisia with Entamoeba moshkovskii in two healthy adults. Entamoeba moshkovskii cysts were distinguished from those of the morphologically identical parasites Entamoeba histolytica and Entamoeba dispar by specific nested polymerase chain reaction and sequencing.
Risk Presented by Copernicia prunifera Palm Trees in the Rhodnius nasutus Distribution in a Chagas Disease-endemic Area of the Brazilian Northeast
Authors: Lima Marli M. , Coutinho Carolina F. S. , Gomes Taís F. , Oliveira Tiago G. , Duarte Rosemere , Borges-Pereira José , Bóia Márcio N. , Sarquis Otília
Published: September 2018

With the aid of live-bait traps, we studied the risk that Copernicia prunifera palm trees, present in both periurban and rural localities of an endemic Brazilian northeast Chagas disease region, represent to domestic infestation by Rhodnius nasutus. In this area, this important vector has been encountered harboring and transmitting Trypanosoma cruzi, the etiologic agent of the American trypanosomiasis, to mammals, possibly including humans. Results indicate that this bug colonizes C. prunifera palm trees of both regions, mainly in dry seasons, and is infected with high levels of T. cruzi. Although more triatomines were captured in rural areas, proportionally the number of infected bugs from peri-urban regions was much higher. Herein we address the epidemiologic implications and challenge for the Brazilian health authorities to control the disease in this region, where the native palm trees have been largely destroyed causing a severe disturbance in the environmental equilibrium.
Use of a Rapid Test on Umbilical Cord Blood to Screen for Trypanosoma cruzi Infection in Pregnant Women in Argentina, Bolivia, Honduras, and México
Authors: Sosa-Estani Sergio , Gamboa-León Miriam Rubi , del Cid-Lemus Jaime , Althabe Fernando , Alger Jackeline , Almendares Olivia , Cafferata María L. , Chippaux Jean-Philippe , Dumonteil Eric , Gibbons Luz , Padilla-Raygoza Nicolás , Schneider Dominique , Belizán José M. , Buekens Pierre , _ _
Published: September 2018

We conducted a cross-sectional study of Chagas disease in five endemic areas in Argentina, Bolivia, Honduras, and México to estimate the prevalence of Trypanosoma cruzi–specific antibodies in pregnant women, and to assess the use of a rapid test (Chagas Stat-Pak) to screen for T. cruzi infection at the time of delivery. The prevalence of antibodies to T. cruzi measured by enzyme-linked immunosorbent assay (ELISA) in maternal blood was 5.5% (a range of 0.8–28.8% among the countries) in 2,495 women enrolled. Compared with ELISA in maternal blood samples, the Chagas Stat-Pak rapid test sensitivity and specificity in umbilical cord blood were 94.6% and 99.0%, respectively. These results show the ability for a rapid determination of the presence of T. cruzi–specific antibodies in umbilical cord blood as a pragmatic strategy to screen for infection in pregnant women.
Analyses of Vaccination Protocols for Leptospira interrogans Serovar Autumnalis in Hamsters
Authors: Srikram Amporn , Wongratanacheewin Surasakdi , Puapairoj Anucha , Wuthiekanun Vanaporn , Sermswan Rasana W.
Published: September 2018

Leptospirosis, caused by Leptospira spp., is a zoonotic disease found worldwide. Killed whole cell leptospiral vaccines have been used as effective vaccines to elicit specific antibodies for protection. However, the involvement of cytokine responses after vaccination is not well characterized. Hamsters were immunized with killed L. interrogans serovar Autumnalis before challenge to study cytokine mRNA expression levels (interferon [IFN]-γ, tumor necrosis factor [TNF]-α, interleukin [IL]-10, and IL-4). Vaccinated groups showed 92–100% survival rates, whereas control hamsters died within 6–10 days. However, live organisms were detected in vaccinated groups, and mild to moderate pathology was observed early in infection. IFN-γ and TNF-α mRNA expression levels correlated with the severity of infection and lung pathology, whereas IL-4 and IL-10 expression levels were significantly higher in vaccinated groups. In summary, commonly used vaccines changed the cytokine profiles and protected hamsters from death but failed to stimulate sterile immunity and were unable to prevent the occurrence of pathology.
Serologic Survey of the Sentinel Animals for Plague Surveillance and Screening for Complementary Diagnostic Markers to F1 Antigen by Protein Microarray
Authors: Li Bei , Guo Ying , Guo Zhaobiao , Liang Yun , Zhu Ziwen , Zhou Qing , Yan Yanfeng , Song Zhizhong , Yang Ruifu
Published: September 2018

Plague is a deadly infectious disease caused by the gram-negative bacterium, Yersinia pestis. In 2005, five plague patients were confirmed in the Yulong County of the Yunnan Province, China. In this study, the serologic survey of > 2,900 serum samples from domestic dogs and cats in and around the county, where human plague occurred, confirmed that domestic dogs and cats could serve as sentinel animals for plague surveillance. Meanwhile, the antibody responses in the infected dogs and cats were profiled by microarray containing 218 proteins of Y. pestis. In addition to F1, LcrV, YPCD1.28c, and YPO2118 induced humoral responses in all or most of the individuals, providing complementary candidates to F1 antigen for diagnostic markers of plague.
Prevention of Blood-borne Diseases in Bolivia, 1993–2002
Authors: Schmunis Gabriel A. , Rodriguez Gloria , Coenen Jan , Bellorin Enrique Gil , Gianella Alberto
Published: September 2018

This report shows the outcome of a coordinated effort by locals, foreign institutions, and an international agency, from 1996–2002, aimed at preventing transmission of blood-borne diseases in Santa Cruz, Bolivia. From 2001–2002, testing the donor pool for HIV prevented transfusion of 32 infected units and 29 infections. With 100% screening coverage, 196 hepatitis B virus (HBV)-infected units were discarded, and 177 infections of HBV were prevented between 1999 and 2002. Incomplete screening for hepatitis C virus (HCV) may have tainted nine units of blood and generated eight HCV infections in 1999. On the other hand, 600 units infected with HCV were discarded, and 540 HCV infections were prevented between 1999 and 2002. Screening for Chagas disease prevented transfusion of 10,661 tainted units and 2,133 infections from 1999 to 2002. From 1996–2002, the investment was US$1,108,000.
Concurrent Infection with Heligmosomoides polygyrus Modulates Murine Host Response against Plasmodium berghei ANKA Infection
Authors: Tetsutani Kohhei , Ishiwata Kenji , Torii Motomi , Hamano Shinjiro , Hisaeda Hajime , Himeno Kunisuke
Published: September 2018

We investigated whether concurrent infection with Heligmosomoides polygyrus, an intestinal nematode, modulated anti-malaria parasite immunity and development of experimental cerebral malaria (ECM) in mice. The C57BL/6 mice infected with Plasmodium berghei ANKA showed typical symptoms of ECM. Interestingly, preceding H. polygyrus infection did not alter ECM development, despite accelerated P. berghei growth in vivo. Our observation provides a new insight that ECM can be induced in a fashion independent of the immune responses affected by concurrent H. polygyrus. Differentiation between protective immunity and infection-associated host-damaging inflammatory response is urgently required for understanding the pathogenesis of cerebral malaria.
Rickettsia felis Outer Membrane Protein A: A Potential Tool for Diagnosis of Patients with Flea-Borne Spotted Fever
Authors: Zavala-Castro Jorge E. , Dzul-Rosado Karla R. , León Juan José Arias , Walker David H. , Zavala-Velázquez Jorge E.
Published: September 2018

Rickettsia felis infection in humans has been detected worldwide, causing an illness that could be confused with other viral and bacterial infections such as dengue fever. Despite the high incidence of infection in humans, reservoirs, and vectors, the definitive diagnosis of R. felis infection currently requires polymerase chain reaction and sequencing because its antigens are closely related to other rickettsiae, making serologic diagnosis problematic. In this work, we report the immune reactivity of sera from four patients infected with R. felis with recombinant peptides representing regions of outer membrane protein A of R. felis.
Severe, Symptomatic Hypomagnesemia in Acute Leptospirosis
Authors: Spichler Anne , Athanazio Daniel A. , Furtado Juvencio , Seguro Antonio , Vinetz Joseph M.
Published: September 2018

We report a case of severe hypomagnesemia in non-oliguric acute renal failure caused by leptospirosis that required large doses of magnesium replacement during the acute phase of disease. Biochemical studies confirmed kidney-related magnesium wasting and the mechanisms of this defect are discussed. Magnesium imbalance with its attendant clinical complications occurs in leptospirosis and should be monitored and treated aggressively in cases of leptospirosis-induced non-oliguric acute kidney injury.
Detection of Salmonella enterica Serotype Typhimurium DT104 in Mozambique
Authors: Ruiz Joaquim , Herrera-Leon Silvia , Mandomando Inacio , Macete Eusebio , Puyol Laura , Echeita Aurora , Alonso Pedro L.
Published: September 2018

The spread of Salmonella enterica serotype Typhimurium definitive phage type DT104 in sub-Saharan Africa is a public health concern. We obtained two isolates of S. typhimurium DT104 from blood cultures of infants with malaria in Mozambique. Both isolates contained Salmonella genomic island 1A and had the same pulsed-field gel electrophoresis PulseNet pattern (STYMXB.0005). Results showed the need for continuous surveillance of Salmonella spp. serotypes circulating in this area.
Stable Prevalence of Powassan Virus in Ixodes scapularis in a Northern Wisconsin Focus
Authors: Brackney Doug E. , Nofchissey Robert A. , Fitzpatrick Kelly A. , Brown Ivy K. , Ebel Gregory D.
Published: September 2018

Deer tick virus (DTV), a variant of Powassan virus (POWV), appears to be maintained in nature in an enzootic cycle between Ixodes scapularis ticks and small mammals. Although POWV infection of human beings is rare, a recent report suggests increasing incidence and the possibility that POWV may be an emerging tick-borne zoonosis. Therefore, we assessed the long-term stability of the POWV transmission cycle in northwestern Wisconsin. Adult I. scapularis and Dermacentor variabilis were collected from Hayward and Spooner, Wisconsin, screened for infection by reverse transcriptase polymerase chain reaction (RT-PCR), and virus was isolated. Seventeen of 1,335 (1.3%) of I. scapularis and 0 of 222 (0%) of D. variabilis ticks were infected. All isolated virus belonged to the DTV genotype of POWV. These findings suggest stable transmission of POWV in this focus over ten years and highlight the potential for this agent to emerge as a public health concern.
Elevated Levels of Alanine Aminotransferase and Hepatitis A in the Context of a Pediatric Malaria Vaccine Trial in a Village in Mali
Authors: Ellis Ruth D. , Dicko Alassane , Sagara Issaka , Kamate Beh , Guindo Ousmane , Niambele Mohamed Balla , Sogoba Moussa , Doumbo Ogobara
Published: September 2018

A Phase 1 study of the apical membrane antigen malaria vaccine AMA1-C1/Alhydrogel was conducted in 2–3-year-old children in a village in Mali. A high frequency of elevated levels of alanine aminotransferase (ALT) caused by hepatitis A was seen, with 8 of 36 children diagnosed by specific IgM antibody over the course of the study. Hepatitis A is a common cause of asymptomatic elevations of ALT levels in children, particularly in less-developed settings. Investigators should be aware of the frequency of hepatitis A in this age group to guard against inadvertently facilitating transmission at study facilities and to properly evaluate symptomatic or asymptomatic elevations of ALT levels.
Modeling CD4+ Cell Count Increase Over a Six-Year Period in HIV-1–Infected Patients on Highly Active Antiretroviral Therapy in Senegal
Authors: De Beaudrap Pierre , Etard Jean-François , Diouf Assane , Ndiaye Ibrahima , Guèye Ndèye Fatou , Guèye Pape Mandoumbé , Sow Papa Salif , Mboup Souleymane , Ndoye Ibra , Ecochard René , Eric Delaporte , _ _
Published: September 2018

To assess the extents and determinants of long-term CD4 cell increases after initiation of antiretroviral therapy (ART), changes in CD4 cell counts were analyzed in a cohort of HIV-1–infected Senegalese using a mixed-effects model. After a median follow-up of 54 months, an average of 483 CD4 cells/mm3 (95% confidence interval [CI] = 331; 680) was reached. The average asymptote level was ~421 cells/mm3 (95% CI = 390; 454) in patients with < 200 cells/mm3 at baseline and ~500 cells/mm3 in patients with > 200 cells/mm3. The independent predictors of long-term CD4 cell reconstitution were the baseline CD4 cell count and the monthly average viral load over the entire follow-up. This good long-term immune reconstitution, optimal in subjects with low average viral loads and > 200 CD4 cells/mm3 at baseline, argues in favor of the earliest possible access to ART and underlines the importance of strict compliance with the treatment.
Methemoglobinemia and Adverse Events in Plasmodium vivax Malaria Patients Associated with High Doses of Primaquine Treatment
Authors: Carmona-Fonseca Jaime , Álvarez Gonzalo , Maestre Amanda
Published: September 2018

Primaquine (PQ) is recommended to prevent relapses in patients with Plasmodium vivax malaria infection. However, treatment with PQ causes methemoglobinemia. In this study, we measured the methemoglobin (MetHB) levels in three groups of subjects who received PQ treatment at 0.58, 0.83, or 1.17 mg/kg/d. A total of 112 subjects were studied. MetHB levels were detected at ≥ 4% in 46–50% 1 day after PQ treatment in all three groups and 4–9% of subjects had MetHB levels ≥ 4% 15 days after treatment. Only subjects receiving the highest doses of PQ had mild and brief adverse events, and 17% of them were associated with treatment. We conclude that when PQ is administered under certain conditions (i.e., normal glucose-6-phosphate dehydrogenase activity, in non-pregnant subjects and with a light meal), daily doses as high as 1.17 mg/kg do not represent a serious risk of high MetHB levels to patients.
Serologic Evidence of Human Ehrlichiosis in Peru
Authors: Moro Pedro L. , Shah Jyotsna , Li Olga , Gilman Robert H. , Harris Nick , Moro Manuel H.
Published: September 2018

A serosurvey for human ehrlichiosis caused by Ehrlichia chaffeensis and Anaplasma phagocytophilum was performed in different regions of Peru by using indirect immunofluorescence assays (IFAs). Regions included an urban community in a shantytown in Lima (Pampas) and three rural communities located on the northern coast of Peru (Cura Mori), in the southern Peruvian Andes (Cochapata), and in the Peruvian jungle region (Santo Tomas). An overall E. chaffeensis seroprevalence of 13% (21 of 160) was found by IFA. Seroprevalences in females and males was 15% (16 of 106) and 9% (5 of 53), respectively. Seroprevalences in Cura Mori, Cochapata, Pampas, and Santo Tomas were 25% (10 of 40), 23% (9 of 40), 3% (1 of 40), and 3% (1 of 40), respectively. Seroprevalences in Cura Mori and Cochapata were significantly higher than in Santo Tomas or Pampas (P < 0.01). No sera were reactive to A. phagocytophilum. These findings suggest that human infection with E. chaffeensis occurs in Peru. Further studies are needed to characterize Ehrlichia species in Peru, their vectors and their clinical significance.
Host Selection by Culex pipiens Mosquitoes and West Nile Virus Amplification
Authors: Hamer Gabriel L. , Kitron Uriel D. , Goldberg Tony L. , Brawn Jeffrey D. , Loss Scott R. , Ruiz Marilyn O. , Hayes Daniel B. , Walker Edward D.
Published: September 2018

Recent field studies have suggested that the dynamics of West Nile virus (WNV) transmission are influenced strongly by a few key super spreader bird species that function both as primary blood hosts of the vector mosquitoes (in particular Culex pipiens) and as reservoir-competent virus hosts. It has been hypothesized that human cases result from a shift in mosquito feeding from these key bird species to humans after abundance of the key birds species decreases. To test this paradigm, we performed a mosquito blood meal analysis integrating host-feeding patterns of Cx. pipiens, the principal vector of WNV in the eastern United States north of the latitude 36°N and other mosquito species with robust measures of host availability, to determine host selection in a WNV-endemic area of suburban Chicago, Illinois, during 2005–2007. Results showed that Cx. pipiens fed predominantly (83%) on birds with a high diversity of species used as hosts (25 species). American robins (Turdus migratorius) were marginally overused and several species were underused on the basis of relative abundance measures, including the common grackle (Quiscalus quiscula), house sparrow (Passer domesticus), and European starling (Sturnus vulgaris). Culex pipiens also fed substantially on mammals (19%; 7 species with humans representing 16%). West Nile virus transmission intensified in July of both years at times when American robins were heavily fed upon, and then decreased when robin abundance decreased, after which other birds species were selected as hosts. There was no shift in feeding from birds to mammals coincident with emergence of human cases. Rather, bird feeding predominated when the onset of the human cases occurred. Measures of host abundance and competence and Cx. pipiens feeding preference were combined to estimate the amplification fractions of the different bird species. Predictions were that approximately 66% of WNV-infectious Cx. pipiens became infected from feeding on just a few species of birds, including American robins (35%), blue jays (17%, Cyanocitta cristata), and house finches (15%, Carpodacus mexicanus).
Contemporary Neurosurgical Approaches to Neurocysticercosis
Authors: Rangel-Castilla Leonardo , Serpa Jose A. , Gopinath Shankar P. , Graviss Edward A. , Diaz-Marchan Pedro , White A. Clinton
Published: September 2018

Neurocysticercosis (NCC) includes a wide spectrum of illnesses. Newer neurosurgical approaches are being applied to NCC. Although clinical trials are leading to a consensus on medical management, fewer data address neurosurgical approaches. We reviewed all neurocysticercosis patients evaluated by neurosurgery at Ben Taub General Hospital, Houston, Texas, between August 1997 and December 2005. From 31 patients that had a neurosurgical evaluation, 16 patients were treated with shunts (5 had shunt failure requiring revision), 13 by surgical resection of cysts (9 underwent craniotomy and 4 endoscopy), and 2 by medical therapy. A fifth endoscopy was performed in one patient with shunt failure. None of the endoscopic patients needed another intervention. Despite the availability of anti-parasitic and anti-inflammatory therapies, neurosurgery continues to play an important role in the management of selected cases of NCC. In contrast to the high rate of shunt failure, neuroendoscopy seems to be associated with higher success rate than any other neurosurgical approach.
Sensitivities and Specificities of Diagnostic Tests and Infection Prevalence of Schistosoma haematobium Estimated from Data on Adults in Villages Northwest of Accra, Ghana
Authors: Koukounari Artemis , Webster Joanne P. , Donnelly Christl A. , Bray Bethany C. , Naples Jean , Bosompem Kwabena , Shiff Clive
Published: September 2018

Substantial uncertainties surround the sensitivities and specificities of diagnostic techniques for urinary schistosomiasis. We used latent class (LC) modeling to address this problem. In this study, 220 adults in three villages northwest of Accra, Ghana were examined using five Schistosoma haematobium diagnostic measures: microscopic examination of urine for detection of S. haematobium eggs, dipsticks for detection of hematuria, tests for circulating antigens, antibody tests, and ultrasound scans of the urinary system. Testing of the LC model indicated non-invariance of the performance of the diagnostic tests across different age groups, and measurement invariance held for males and females and for the three villages. We therefore recommend the use of LC models for comparison between and the identification of the most accurate schistosomiasis diagnostic tests. Furthermore, microscopy and hematuria dipsticks were indicated through these models as the most appropriate techniques for detection of S. haematobium infection.
Impact of Diabetes Mellitus on Treatment Outcomes of Patients with Active Tuberculosis
Authors: Dooley Kelly E. , Tang Tania , Golub Jonathan E. , Dorman Susan E. , Cronin Wendy
Published: September 2018

Diabetes mellitus (DM) is an emerging chronic health condition of developed and developing countries. We conducted a retrospective cohort study of patients with active, culture-confirmed tuberculosis (TB) in Maryland to determine the impact of DM on TB treatment outcomes. Of 297 TB patients, 42 (14%) had DM. Patients with diabetes had 2.0 times higher odds of death than patients without diabetes (95% confidence interval [CI] 0.74–5.2, P = 0.18). Adjusting for human immunodeficiency virus (HIV), age, weight, and foreign birth, the odds of death were 6.5 times higher in patients with diabetes than patients without diabetes (95% CI 1.1–38.0, P = 0.039). In pulmonary TB patients, time to sputum culture conversion was longer in patients with diabetes than patients without diabetes (median 49 versus 39 days, P = 0.09). Two-month culture conversion proportions were similar (70% and 69%). Treatment failure occurred in 4.1% of patients without diabetes and 6.7% of patients with diabetes (P = 0.51). In conclusion, DM was a risk factor for death in Maryland TB patients. There was a trend toward increased time to culture conversion; two-month culture conversion proportions, however, were similar.