The Oral Host-Microbial Interactome: An Ecological Chronometer of Health?

An increasing number of studies reveal that host-microbial interactome networks are coordinated, impacting human health and disease. Recently, several lines of evidence have revealed associations between the acquisition of a complex microbiota and adaptive immunity, supporting that host-microbiota symbiotic relationships have evolved as a means to maintain homeostasis where the role of the microbiota is to promote and educate the immune system. Here, we hypothesize an oral host-microbial interactome that could serve as an ecological chronometer of health and disease, with specific focus on caries, periodontal diseases, and cancer. We also review the current state of the art on the human oral microbiome and its correlations with host innate immunity, and host cytokine control, with the goal of using this information for disease prediction and designing novel treatments for local and systemic dysbiosis. In addition, we discuss new insights into the role of novel host-microbial signals as potential biomarkers, and their relevance for the future of precision dentistry and medicine.

Prevention of mother-to-child transmission of hepatitis B virus: protocol for a one-arm, open-label intervention study to estimate the optimal timing of tenofovir in pregnancy

INTRODUCTION

Hepatitis B virus (HBV) remains a public health threat and the main route of transmission is from mother to child (MTCT). Tenofovir disoproxil fumarate (TDF) treatment can reduce MTCT of HBV although the optimal timing to attain undetectable HBV DNA concentrations at delivery is unknown. This protocol describes the procedures following early initiation of maternal TDF prior to 20 weeks gestation to determine efficacy, safety and feasibility of this approach in a limited-resource setting.

METHODS AND ANALYSES

One hundred and seventy pregnant women from the Thailand-Myanmar border between 12 and <20 weeks gestational age will be enrolled into a one-arm, open-label, TDF treatment study with cessation of TDF 1 month after delivery. Sampling occurs monthly prenatal, at birth and at 1, 2, 4 and 6 months post partum. Measurement of tenofovir concentrations in maternal and cord plasma is anticipated in 10-15 women who have detectable HBV DNA at delivery and matched to 20-30 women with no detectable HBV DNA. Infant HBsAg status will be determined at 2 months of age and HBV DNA confirmed in HBsAg positive cases. Adverse events including risk of flare and adherence, based on pill count and questionnaire, will be monitored. Infants will receive HBV vaccinations at birth, 2, 4 and 6 months and hepatitis B immunoglobulin at birth if the mother is hepatitis B e antigen positive. Infant growth and neurodevelopment at 6 months will be compared with established local norms.

ETHICS AND DISSEMINATION

This study has ethical approval by the Ethics Committee of the Faculty of Tropical Medicine, Mahidol University (FTM ECF-019-06), Johns Hopkins University (IRB no: 00007432), Chiang Mai University (FAM-2559-04227), Oxford Tropical Research Ethics Committee (OxTREC Reference: 49-16) and by the local Tak Community Advisory Board (TCAB-02/REV/2016). The article will be published as an open-access publication.

TRIAL REGISTRATION NUMBER

NCT02995005, Pre-results.

Prevalence of HIV infection and related risk factors among young Thai men between 2010 and 2011

Introduction

Understanding the current epidemiology of human immunodeficiency virus (HIV) infection in Thailand will facilitate more effective national HIV prevention programs. This study aimed to determine the prevalence and risk factors for HIV infection among young Thai men.

Methods

A total survey was conducted of Royal Thai Army new conscripts, participating in the national HIV surveillance in November 2010 and May 2011. Behavioral risk factors for HIV infection were determined using a standardized survey questionnaire in the total study population and men who have sex with men (MSM) subgroup.

Results

A total of 301 (0.5%) HIV infected young Thai men were identified from the total study population (63,667). Independent risk factors associated with HIV infection among the total study population included being single (adjusted Odds Ratio [AOR] 1.6, 95% Confidence Interval [CI] 1.1–2.2), having no formal education (AOR 6.5, 95% CI 2.3–18.4) or a bachelor’s degree (AOR 1. 8, 95% CI 1.0–3.0), engaging in bisexual (AOR 3.7, 95% CI 2.4–5. 6) or exclusively homosexual activity (AOR 14.4, 95% CI 10.4–19.8), having a history of Sexually Transmitted Infection (STI) (AOR 2.3, 95% CI 1.6–3.3) and having sex in exchange for gifts/money (AOR 2.0, 95% CI 1. 5–2.8). A total of 4,594 (7.9%) MSM were identified, of which 121 (2.6%) were HIV infected. The prevalence of HIV infection among MSM in urban (2.8%) and rural (2.4%) areas were relatively comparable (p-value = 0.44). Of the identified MSM, 82.5% reported having sexual desire with females only. Risk factors associated with HIV infection in the MSM subgroup included living in the western region (AOR 3.5, 95% CI 1.2–10.4), having a bachelor’s degree (AOR 2.7, 95% CI 1.2–5.7), having a history of exclusive receptive (AOR 3.6, 95% CI 1.6–7.7) or versatile anal sex (AOR 4.7, 95% CI 3.0–7.5) and history of having sex in exchange for gifts/money (AOR 2.3, 95% CI 1.5–3.5).

Conclusion

The prevalence of HIV infection among young Thai men has continued to be below 0.5% in 2010 and 2011. High risk sexual activity, including MSM, played a major role in the HIV epidemic among this population. Effective HIV prevention programs should cover MSM who have heterosexual desire as well as having sex in exchange for gifts/money and be implemented in both urban and rural areas.

Durable HIV Suppression Among People Who Inject Drugs From a Community-Based Cohort Study in Baltimore, Maryland, 1997-2017

People who inject drugs (PWID) face disparities in human immunodeficiency virus (HIV) treatment outcomes and may be less likely to achieve durable viral suppression. We characterized transitions into and out of viral suppression from 1997 to 2017 in a long-standing community-based cohort study of PWID, the AIDS Link to Intravenous Experience (ALIVE) Study, analyzing HIV-positive participants who had made a study visit in or after 1997. We defined the probabilities of transitioning between 4 states: 1) suppressed, 2) detectable, 3) lost to follow-up, and 4) deceased. We used multinomial logistic regression analysis to examine factors associated with transition probabilities, with a focus on transitions from suppression to other states. Among 1,061 participants, the median age was 44 years, 32% were female, 93% were African-American, 59% had recently injected drugs, and 28% were virologically suppressed at baseline. Significant improvements in durable viral suppression were observed over time; however, death rates remained relatively stable. In adjusted analysis, injection drug use and homelessness were associated with increased virological rebound in earlier time periods, while only age and race were associated with virological rebound in 2012-2017. Opioid use was associated with an increased risk of death following suppression in 2012-2017. Despite significant improvements in durable viral suppression, subgroups of PWID may need additional efforts to maintain viral suppression and prevent premature mortality.

Epidemiology of Genotype 1 and 2 Hepatitis E Virus Infections

Hepatitis E virus (HEV) genotypes 1 and 2 are responsible for the majority of acute viral hepatitis infections in endemic areas in South Asia and sub-Saharan Africa. In addition to frequent sporadic illnesses throughout the year, these viruses often cause large epidemics in association with monsoon rains in Asia or during humanitarian crises in Africa. Clinical hepatitis commonly involves adults more often than young children, with an overall mortality of ∼1%. However, the mortality among pregnant women is often 30% or higher. HEV infection in pregnant women frequently leads to infant mortality or premature delivery. Hepatitis E is an important, yet largely neglected, global public health problem.

Long-term Antibody Persistence After Hepatitis E Virus Infection and Vaccination in Dongtai, China

Background

Hepatitis E virus (HEV) is of global significance. HEV is a common cause of acute hepatitis in China. One of the major unanswered questions about HEV is the persistence of antibodies after infection and vaccination.

Methods

We examined antibody persistence 6.5 years after HEV exposures through natural infection and vaccination. Ninety-seven vaccine recipients and 70 individuals asymptomatically infected with HEV enrolled in the phase III HEV239 vaccine trial in Dongtai, China, were revisited.

Results

Antibody loss was 23.4% (95% confidence interval [CI], 17.1%-30.5%), with a nonsignificantly higher percentage of loss among those naturally infected (30.0%; 95% CI, 19.6%-42.1%) than those vaccinated (18.6%; 95% CI, 11.4%-27.7%; P = .085). Age and gender were not associated with antibody persistence. Only 2 people (1.2%) self-reported medically diagnosed jaundice or hepatitis-like illness in the last 10 years, both of whom had persistent antibodies. Contact with a jaundice patient and injectable contraceptive use were marginally associated with loss of detectable anti-HEV antibodies (P = .047 and .082, respectively), whereas transfusion was marginally associated with antibody persistence (P = .075).

Conclusions

Antibody loss was more common among those naturally infected compared with those vaccinated. However, none of the characteristics examined were strongly associated with antibody loss, suggesting that factors not yet identified may play a more important role in antibody loss. Long-term postvaccination antibody persistence is currently unknown and will be an important consideration in the development of policies for the use of the highly efficacious HEV vaccine. ClinicalTrials.gov registration.  NCT01014845.

An outbreak of HIV infection among people who inject drugs linked to injection of propofol in Taiwan

INTRODUCTION

The aim of this study was to report an HIV outbreak related to propofol-injection and the impact of regulating propofol on the HIV epidemic among people who inject drugs (PWID).

METHODS

A retrospective cohort study of 252 PWID who were diagnosed with an HIV infection between 2014 and 2017 in Taiwan. The propofol information was collected by routine epidemic surveillance and interviews. We linked several national databases to collect other related factors, including methadone maintenance treatment (MMT) attendance and incarceration. The serums were tested for recent infection by the LAg-avidity EIA assay and relationship of the trains by the Phylogenetic tree analysis. Analyses were conducted using the R Surveillance package for retrospective modeling for outbreak detection. A multiple logistic regression was used to evaluate the association between propofol-injection and other related factors.

RESULTS

There were 28 cases reported with propofol-injection, all of which were reported in Central Taiwan. A total of 11 (50%) cases among 22 propofol-injectors with serums were recent infections, which were higher than that 33 (23.4%) of non-propofol group. The phylogenetic tree indicated that 6 propofol-injectors were grouped together with the same cluster in circular. The HIV epidemic curve among PWID revealed an outbreak of 82 in 2015, which then decreased to 43 in 2016 after propofol began to be regulated as a Schedule 4 controlled drug in August 2015. In a multiple logistic regression, attendance at methadone clinics was associated with a significantly higher risk for propofol-injection (adjusted OR = 2.43, 95% CI = 0.98-5.98), and HIV reported in the year 2015 was associated with an increased risk of propofol-injection (adjusted OR = 4, 95% CI = 1.08-14.86).

CONCLUSIONS

Our data indicate that the government regulation of propofol as a controlled drug strategy was associated with significant reduction in the spread of HIV among PWID.

Probable transmission of hepatitis E virus (HEV) via transfusion in the United States

BACKGROUND

Hepatitis E virus (HEV) can inapparently infect blood donors. To assess transfusion transmission of HEV in the United States, which has not been documented, a donor-recipient repository was evaluated.

STUDY DESIGN AND METHODS

To identify donations that contained HEV RNA and were linked to patient-recipients with antibody evidence of HEV exposure, we assayed samples from the Retrovirus Epidemiology Donor Study (REDS) Allogeneic Donor and Recipient repository that represents 13,201 linked donations and 3384 transfused patients. Posttransfusion samples, determined to contain IgG anti-HEV by enzyme-linked immunosorbent assay, were reassayed along with corresponding pretransfusion samples for seroconversion (incident exposure) or at least fourfold IgG anti-HEV increase (reexposure). HEV-exposed patients were linked to donations in which HEV RNA was then detected by reverse-transcription quantitative polymerase chain reaction, confirmed by transcription-mediated amplification, and phylogenetically analyzed as subgenomic cDNA sequences.

RESULTS

Among all patients, 19 of 1036 (1.8%) who had IgG anti-HEV before transfusion were reexposed; 40 of 2348 (1.7%) without pretransfusion IgG anti-HEV seroconverted. These 59 patients were linked to 257 donations, 1 of which was positive by reverse-transcription quantitative polymerase chain reaction and transcription-mediated amplification. Plasma from this donation contained 5.5 log IU/mL of HEV RNA that grouped with HEV genotype 3, clade 3abchij. The patient-recipient of RBCs from this donation had a greater than eightfold IgG increase; however, clinical data are unavailable.

CONCLUSIONS

This is the first report of probable HEV transmission via transfusion in the United States, although it has been frequently observed in Europe and Japan. Additional data on the magnitude of the risk in the United States are needed.

Knowledge regarding hepatitis B mother-to-child transmission among healthcare workers in South China

To determine the knowledge regarding hepatitis B virus (HBV) mother-to-child transmission (MTCT) and its prevention and treatment among healthcare workers (HCWs) in Guangdong Province, China, an HBV endemic area. An HBV knowledge questionnaire was administered to 900 HCWs from the 3rd Affiliated Hospital of Sun Yat-Sen University and 2 rural hospitals in Guangdong Province. The 27 items in the questionnaire fell into 3 sections: HBV MTCT general knowledge, respondents' practices of preventing HBV MTCT and awareness of the resources of preventing HBV MTCT. The data collected were coded and analysed using SPSS software version 20. In total, 503 of 900 HCWs responded to the survey (response rate: 55.9%). Eighty-four individuals responded correctly to all of the knowledge questions: 58 were doctors, and 26 were nurses (P < .05). Doctors more often performed practices than nurses (t = 3.591, P < .01). Participants from the infectious disease department demonstrated a significantly higher proportion of correct answers and resource utilization than other specialties (χ²  = 14.052, 7.998, P < .01). In terms of the average knowledge score, t test or ANOVA showed that there were significant differences between the specialty groups (t = 3.110, P < .01), hospital level groups (t = 2.337, P < .05) and age groups (F = 3.020, P < .05). Respondents' initiative increased with hospital level and age (t = 2.993, 7.493, P < .01). A considerable percentage of HCWs has misconceptions about HBV MTCT. Healthcare workers, in particular nurses, those working in noninfectious disease departments or township hospitals and younger medical staff, lack systematic and comprehensive knowledge about HBV MTCT and are in urgent need of HBV-related training.

A Ten Year Immunopersistence Study of Hepatitis E Antibodies in Rural Bangladesh

Hepatitis E virus (HEV) is a major cause of acute, viral hepatitis in Southeast Asia. Several studies have suggested that antibody persistence after HEV infection may be transient, possibly increasing the risk of re-infection and contributing to the frequency of outbreaks in HEV endemic regions. The specific conditions under which antibodies to HEV are lost, or "sero-reversion" occurs, are poorly understood. Here, one hundred participants from population-based studies in rural Bangladesh were revisited in 2015, ten years after a documented HEV infection to examine long-term antibody persistence. Twenty percent (95% confidence interval: 12.0, 28.0) no longer had detectable antibodies at follow-up, suggesting that antibodies generally persist for at least a decade after infection in rural Bangladesh. Those who were seronegative at follow-up were generally younger at infection than those who remained positive (14.4 years versus 33.6 years, P > 0.0001). This age-dependent antibody loss could partially explain cross-sectional sero-prevalence data from South East Asia where children have reportedly low antibody prevalence. The results of this study provide new insight into the immunological persistence of HEV infection in a micronutrient deficient rural population of South Asia, highlighting the importance of age at infection in the ability to produce long-lasting antibodies against HEV.

The Importance of Military Conscripts for Surveillance of Human Immunodeficiency Virus Infection and Risk Behavior in Thailand

BACKGROUND

The epidemic of Human Immunodeficiency Virus (HIV) infection in Thailand began in 1988 among Injection Drug Users (IDUs) in Bangkok. It soon spread to other populations, especially Female Sex Workers (FSWs) and men attending STD clinics. Routine serologic surveillance for HIV began among military conscripts in 1991. The HIV seroprevalence data from military conscripts provided national surveillance data, since the entire population of 21 year old men were conscripted for 2 years' service in the military by a random process during which 10% of men were selected. Men with a history of injection drug use, or other risk behavior for HIV infection were included.

METHODS

HIV seropositive data were analyzed from cohorts of men who were conscripted between 1991 and 2011. Comprehensive behavioral risk data were obtained from the men in these cohorts in order to evaluate behavior changes in response to the evolving HIV/AIDS epidemic. After the Ministry of Public Health established the "100% condom" program in 1991, behavioral data and HIV prevalence and incidence data from military conscripts were important for evaluating the program.

RESULTS

The HIV prevalence among Royal Thai Army (RTA) conscripts in 1991 was 4.0%. However, the prevalence was 11.2% among conscripts from the upper Northern provinces. A history of sex with a female sex worker (FSW) was reported by 85.8% of men in 1991; having had sex with a FSW was strongly associated with HIV prevalence, OR=7.40 (3.80-14.0). During the next few years, the HIV prevalence decreased progressively, reports of sex with a FWS declined and the use of condoms during sex increased. Also, the incidence of HIV among conscripts while they were in the army decreased. In the cohort enrolled in 1998, the association between a history of sex with a FSW decreased (OR=2.79; 95% CI 1.0-7.8) however the association between a history of injection drug use and HIV prevalence increased substantially (OR=14.47; 95% Ci 3.5-56.6). Among men in cohorts included in 2008-2009, the HIV prevalence was 0.5%. The most important risk behavior reported by men in these cohorts was sex with another man (MSM), adjusted OR=5.3 (95% CI 3.25- 8.65) whereas history of sex with a FSW was less of a risk. In this cohort 39.5% of HIV infected men reported MSM behavior.

CONCLUSION

The sequential data on HIV prevalence and behavioral data from successive large randomly selected national cohorts of young men in Thailand who were conscripted into the Royal Thai Army between 1991 and 2011 has provided critically important surveillance data to monitor the epidemic and evaluate the ongoing effectiveness of public health prevention programs.

The association of elevated alanine aminotransferase levels with hepatitis E virus infections among blood donors in China

BACKGROUND

Transfusion transmission of hepatitis E virus (HEV) is an emerging health risk, yet blood donors are rarely screened for this pathogen. Many blood centers instituted screening of blood donors for elevated levels of alanine aminotransferase (ALT) levels to prevent hepatitis C virus, which has continued in China. We evaluated whether elevated ALT levels were associated with HEV among blood donors in China.

STUDY DESIGN AND METHODS

Blood samples were collected from 9069 qualified volunteer blood donors from four blood centers in China. A total of 5023 had elevated ALT levels, that is, more than 40 IU/L, and 4046 samples had normal ALT. We tested all the 9069 samples for anti-HEV immunoglobulin (Ig)M, anti-HEV IgG, and HEV antigen. Those who were positive for anti-HEV IgM or HEV antigen were tested individually for HEV RNA by polymerase chain reaction.

RESULTS

The prevalence of anti-HEV IgG in donors with elevated ALT levels (33.3%) was higher than those with normal ALT (24.9%; p < 0.01). The prevalence of anti-HEV IgM was similar in donations with increased ALT (1.41%) and normal ALT (1.46%). More ALT-elevated donations were HEV antigen positive, 62 of 5023 (1.23%), than were ALT-normal donations, seven of 4046 (0.17%; p < 0.01). Six donors with elevated ALT levels and acute HEV infection markers (anti-HEV IgM or HEV antigen) were HEV RNA positive.

CONCLUSION

Markers of active infection including HEV antigen and HEV RNA are significantly more common among donors with elevated ALT levels in China. These data support the fact that ALT testing of donors to HEV antigen or HEV RNA would have greater specificity and exclude fewer acceptable donors.

Knowledge of and attitudes towards hepatitis B and its transmission from mother to child among pregnant women in Guangdong Province, China

BACKGROUND

Hepatitis B virus (HBV) infection remains a serious public health problem worldwide. Mother-to-child transmission (MTCT) of HBV is the major mode of transmission in HBV-endemic areas, including China, where little is known about pregnant women's knowledge of and attitudes towards HBV infection and MTCT.

METHODS

A cross-sectional survey, conducted in pregnant women in Guangdong Province, China, measured HBV knowledge and attitudes using a questionnaire, at one tertiary and two rural hospitals.

RESULTS

The total response rate was 94.5% (737/780). Of the 11 knowledge questions, the mean score was 6.73 ± 3.04 (mean ± SD). Most pertinent to preventing MTCT, 53.3% of the respondents did not know that HBV can be transmitted through unprotected sexual intercourse and nearly 20% did not know that HBV can be transmitted from mother to infant. The results of the four attitude questions was better with 83% and 85% being willing to be screened for HBV and let their baby receive HBV vaccine and HBIg, respectively. However, only 16.5% of respondents agreed that they would be willing to take drugs that are known not to harm the fetus to prevent MTCT of HBV. In multivariable analysis, higher education level was associated with better knowledge and attitude scores.

CONCLUSIONS

Knowledge about HBV among pregnant women was poor and needs to be improved to prevent MTCT of HBV. Health education needs to be directed towards pregnant mothers, particularly less educated mothers, in high HBV endemicity settings.

Development of an oral fluid immunoassay to assess past and recent hepatitis E virus (HEV) infection

BACKGROUND

Hepatitis E virus (HEV) infection causes significant morbidity and mortality worldwide, particularly among pregnant women. In clinical settings blood-based testing protocols are commonly used to diagnose HEV infection, but in community settings such invasive sampling can hinder study participation and limit discovery of the ecology and natural history of HEV infection. Oral fluid is a non-invasive biospecimen that can harbor pathogen-specific antibodies and has the potential to replace blood-based testing protocols.

OBJECTIVES

To develop an immunoassay to assess past and recent HEV infection that uses oral fluid instead of serum or plasma.

METHODS

The assay was validated using paired oral fluid and serum samples collected from 141 patients who presented either with (n=76) or without (n=65) symptoms of acute viral hepatitis at a clinical diagnostics center in Dhaka, Bangladesh. The sensitivity and specificity of the oral fluid-based immunoassay for HEV IgG (past HEV infection) and HEV IgA (recent HEV infection) antibodies was calculated in reference to Wantai's (Beijing Wantai) serum-based HEV enzyme-linked immunosorbent assay (ELISA) kits for IgG and IgM antibodies, respectively.

RESULTS

The sensitivity and specificity of the oral fluid-based immunoassay for HEV-IgG antibodies were 98.7% and 98.4%, respectively. The sensitivity and specificity of the oral fluid-based immunoassay for HEV IgA were 89.5% and 98.3%, respectively.

CONCLUSIONS

The high concordance of our non-invasive oral fluid-based immunoassays (HEV IgG and HEV IgA) with commercial high-performance serum HEV ELISA kits (IgG and IgM) means that population-based surveillance of past and recent HEV infection could be expanded to improve understanding of its ecology and natural history.

Status of HBsAg seroprevalence in 15 million rural couples in China: a cross-sectional study

A cross-sectional analysis of prevalence of hepatitis B virus infection (HBV) among rural couples was conducted between 2010 and 2014. Serologic HBV markers, including hepatitis B surface antigen (HBsAg) and e antigen (HBeAg), were tested. Primary outcome of interest comprised HBsAg positivity in couples (both positive: F+M+, only wife positive: F+M−, only husband positive: F−M+), and secondary outcome consisted of prevalence and risk factors of HBsAg positivity among husbands or wives. Of 14,816,300 couples included, 0.7% were F+M+; 6.3% were F−M+; 4.4% were F+M−, resulting in the overall seroprevalence of 11.4%. Individually, 6.1% were HBsAg positive with a higher rate seen in husbands (7.0%) than in wives (5.2%). Wife’s HBeAg(+)/HBsAg (+) (AOR = 2.61), HBeAg(−)/HBsAg (+) (AOR = 2.23), positivity of syphilis (AOR = 1.50), living in a high-risk region (AOR = 1.46) were significantly predictors of HBsAg positivity in husbands. Prevalence and predictors of HBsAg positivity in wives had similar results. Our data show a high burden and discordant pattern of HBV infection in rural couples, and partner’s double positivity of HBeAg and HBsAg was the most significant factor of HBV infection in couples. A comprehensive strategy that emphasizes vaccination and education is needed.

Condom Use During Commercial Sex Among Male Clients of Female Sex Workers in Sichuan China: A Social Cognitive Theory Analysis

There has been little theory-based research focusing on condom use among male clients of female sex workers (CFSW) in China. The current study applied social cognitive theory to condom use behaviors of CFSW in China. Face-to-face structured interviews were conducted among 584 CFSW recruited through snowball sampling. Bivariate and multivariate logistic regression models were applied to examine factors associated with consistent condom use. A minority (30.65 %) of respondents reported using condoms consistently with FSW, and 7 of 12 social cognitive dimensions/subdimensions were found to be significantly influential. The most significant factors were self-efficacy [adjusted prevalence ratio (APR) = 2.11, 95 %, CI = 1.74-2.43] and personal pleasure reduction (APR = 0.3, 95 % CI = 0.15-0.6). HIV-related knowledge, perceived HIV susceptibility, condom cost, condom efficacy, and embarrassment of carrying condoms were not associated with consistent condom uses with FSW. Findings from the current study suggest future prevention programs should target sex venues, and condom access should ensure both quantity and quality. Peer education should focus on knowledge education and peer norms, and knowledge education should include information on HIV infection severity and how to increase pleasure with condom use.

Acute and Chronic Hepatitis E Virus Infection in Human Immunodeficiency Virus-Infected U.S. Women

Exposure to hepatitis E virus (HEV) is common in the United States, but there are few data on prevalence of HEV/human immunodeficiency virus (HIV) coinfection in U.S.

POPULATIONS

We tested 2,919 plasma samples collected from HIV-infected (HIV(+)) women and men enrolled in U.S. cohort studies for HEV viremia using a high-throughput nucleic acid testing (NAT) platform. NAT(+) samples were confirmed by real-time polymerase chain reaction. Samples were selected for testing primarily on the basis of biomarkers of liver disease and immune suppression. Prevalence of HEV viremia was 3 of 2,606 and 0 of 313 in tested plasma samples collected from HIV(+) women and men, respectively. All HEV isolates were genotype 3a. Based on follow-up testing of stored samples, 1 woman had chronic HEV infection for >4 years whereas 2 women had acute HEV detectable at only a single study visit.

CONCLUSIONS

To our knowledge, this is the first reported case of chronic HEV infection in an HIV(+) U.S. individual. We also confirm that chronic HEV infection can persist despite a CD4(+) count >200 cells/mm(3). Overall, though, these data suggest that HEV infection is rare in the HIV(+) U.S. population.

The natural history of recent hepatitis C virus infection among blood donors and injection drug users in the country of Georgia

Introduction

Hepatitis C virus (HCV) infection is a serious health problem in Georgia.

Methods

We conducted a prospective study to identify and characterize the natural history of recent HCV infection since very first days of infection. Recent HCV infection was defined as detectable plasma HCV RNA in the absence of anti-HCV antibodies.

Results

A total of 7600 HCV seronegative blood donors and 3600 HCV seronegative drug users were screened for recent HCV infection. Among them 7 (0.09 %) blood donors and 10 (0.28 %) drug users tested positive for HCV RNA and were classified as having recent HCV infection. Of these 17 patients 4 (23.5 %) spontaneously cleared the virus by the end of 24 week follow-up. Five clinical forms of recent HCV infection were identified during the follow-up. Four patients had symptomatic disease, including 3 patients with jaundice and other clinical symptoms (2 of them cleared virus) and 1 patient only had other symptoms without jaundice. All symptomatic patients had ALT elevation. Three distinct variants of asymptomatic disease were identified in 13 patients: 9 patients had ALT elevation and none cleared the virus; 2 patients developed chronic disease without ALT elevation; 2 patients cleared virus without anti-HCV seroconversion and without ALT elevation; this form can be described as transitory HCV viremia.

Conclusion

Additional studies are needed to define clinical and public health implications of transitory HCV viremia. Our study suggests the need for implementing nucleic acid testing of blood donors and key populations in order to more effectively identify HCV infected persons.

Hepatitis E Virus Infection Among Solid Organ Transplant Recipients at a North American Transplant Center

Background.  Autochthonous hepatitis E virus (HEV) infection has been reported in over 200 solid organ transplant (SOT) recipients since 2006, yet little is known about the burden of HEV among SOT recipients in North America. We performed a retrospective, cross-sectional study to investigate the prevalence and risk factors associated with HEV infection among SOT recipients at our institution. Methods.  Children and adults (n = 311) who received allografts between 1988 and 2012 at the Johns Hopkins Hospital were assessed for evidence of HEV infection by testing posttransplantation serum samples for HEV antibody by enzyme immunoassay and HEV RNA by reverse transcription quantitative polymerase chain reaction. Individuals with evidence of posttransplant HEV infection (presence of anti-HEV immunoglobulin [Ig]M antibody, anti-HEV IgG seroconversion, or HEV RNA) were compared with individuals without evidence of infection and assessed for risk factors associated with infection. Results.  Twelve individuals (4%) developed posttransplant HEV infection. Posttransplant HEV infection was associated with an increased risk for graft rejection (odds ratio, 14.2; P = .03). No individuals developed chronic infection. Conclusions.  Solid organ transplant recipients in the United States are at risk for posttransplant HEV infection. Further studies are needed to characterize environmental risk factors and the risk of HEV infection after SOT in North America.

HLA Class I Alleles Associated with Mortality in Thai Military Recruits with HIV-1 CRF01_AE Infection

In HIV-1-infected patients, variation at the HLA class I locus is associated with disease progression, but few studies have assessed the influence of HLA alleles on HIV-1 CRF01_AE infection, which is dominant in Thailand. We hypothesized that alleles predicted to confer more effective immune responses, such as HLA-B*46, would protect against disease progression. HLA typing was performed on HIV-1 incident cases surviving until 1998-1999 and HIV-1-negative matched controls from Thai army cohorts enrolled between 1991 and 1995. We assessed associations between class I alleles and disease progression subsequent to HLA typing. Ninety-nine HIV-1-incident cases were followed for a median of 3.7 years after HLA typing; during this time, 58 participants died. Two alleles were associated with mortality: HLA B*51 was protective (3-year survival B*51(pos) vs. B*51(neg): 75% vs. 52%; p = 0.034) whereas Cw*04 was deleterious (3-year survival Cw*04(pos) vs. Cw*04(neg): 39% vs. 60%; p = 0.027). HLA-B*46 was not associated with disease progression. Alleles present at different frequencies in HIV-1-incident compared with HIV-1-negative men included HLA-A*02:03, B*35, B*15, and C*08. 1. In conclusion in this Thai army cohort, HLA-B*51 was associated with lower mortality, confirming that this allele, which is protective in clade B HIV-1 infection, has a similar effect on HIV CRF01_AE infection. The deleterious effect of HLA-Cw*04 must be interpreted with caution because it may be in linkage disequilibrium with disease-susceptible HLA-B alleles. We did not find that HLA-B*46 was protective. These findings may inform vaccine development for areas of the world in which HIV-1 CRF01_AE infection is prevalent.

Arsenic exposure and hepatitis E virus infection during pregnancy

BACKGROUND

Arsenic has immunomodulatory properties and may have the potential to alter susceptibility to infection in humans.

OBJECTIVES

We aimed to assess the relation of arsenic exposure during pregnancy with immune function and hepatitis E virus (HEV) infection, defined as seroconversion during pregnancy and postpartum.

METHODS

We assessed IgG seroconversion to HEV between 1st and 3rd trimester (TM) and 3 months postpartum (PP) among 1100 pregnancies in a multiple micronutrient supplementation trial in rural Bangladesh. Forty women seroconverted to HEV and were matched with 40 non-seroconverting women (controls) by age, parity and intervention. We assessed urinary inorganic arsenic plus methylated species (∑As) (µg/L) at 1st and 3rd TM and plasma cytokines (pg/mL) at 1st and 3rd TM and 3 months PP.

RESULTS

HEV seroconverters' urinary ∑As was elevated throughout pregnancy. Non-seroconverters' urinary ∑As was similar to HEV seroconverters at 1st TM but declined at 3rd TM. The adjusted odds ratio (95% confidence interval) of HEV seroconversion was 2.17 (1.07, 4.39) per interquartile range (IQR) increase in average-pregnancy urinary ∑As. Increased urinary ∑As was associated with increased concentrations of IL-2 during the 1st and 3rd TM and 3 months PP among HEV seroconverters but not non-seroconverters.

CONCLUSIONS

The relation of urinary arsenic during pregnancy with incident HEV seroconversion and with IL-2 levels among HEV-seroconverting pregnant women suggests arsenic exposure during pregnancy may enhance susceptibility to HEV infection.

Risk Factors for HIV Infection among Young Thai Men during 2005-2009

Background

Thailand is one of several countries with a continuing generalized HIV epidemic. We evaluated the risk factors for HIV prevalence among 17–29 year old men conscripted by a random process into the Royal Thai Army (RTA) in 8 cohorts from 2005–2009.

Methods

A series of case-cohort studies were conducted among the male RTA conscripts who had been tested for HIV seroprevalence after they were inducted. Men who were HIV positive were compared with a systematic random sample (1 in 30–40) of men from the total population of new conscripts. Each subject completed a detailed risk factor questionnaire.

Results

A total of 240,039 young Thai men were conscripted into the RTA and were screened for HIV seroprevalence between November 2005 and May 2009. Of 1,208 (0.5%) HIV positive cases, 584 (48.3%) men were enrolled into the study. There were 7,396 men who were enrolled as a comparison group. Among conscripts who had an education lower than a college-level, the independent risk factors for HIV infection were age in years (AOR 1.38, 95% CI 1.28–1.48), a history of sex with another man (AOR 3.73, 95% CI 2.70–5.13), HCV infection (AOR 3.89, 95% CI 2.56–5.90), and a history of sex with a female sex worker (FSW) (AOR 1.35, 95% CI 1.10–1.66). Among conscripts who had a college degree, the independent risk factor for HIV infection was a history of sex with another man (AOR 23.04, 95% CI 10.23–51.90). Numbers of sexual partners increased and the age at first sex, as well as the use of condoms for sex with a FSW decreased in successive cohorts.

Conclusion

The HIV seroprevalence among cohorts of 17–29 years old men has remained at about 0.5% overall during 2005–2009. The most significant behavior associated with HIV prevalence was a history of sex with another man. Our data indicate continuing acquisition of HIV among young men in Thailand in recent years, especially among men with a history of same sex behavior.

Two Generations of "Gold Standards": The Impact of a Decade in Hepatitis E Virus Testing Innovation on Population Seroprevalence

Hepatitis E virus (HEV) is a global pathogen responsible for approximately 20 million infections every year in developing countries, yet remains under-recognized. In this population-based cohort study, 1,025 randomly selected participants were enrolled from Matlab, Bangladesh (2004-2005). All participants were tested for HEV antibodies and total immunoglobulin (Ig), using an in-house enzyme immunoassay developed by Walter Reed Army Institute of Research (WRAIR). In 2014, we retested the banked sera of 1,009 of those participants using the Wantai anti-HEV IgG enzyme-linked immunosorbent assay (ELISA). The WRAIR assay estimated the overall population seroprevalence as 26.6% (95% confidence interval [CI]: 24.0, 29.5), whereas the Wantai assay produced significantly higher estimated seroprevalence, 46.7% (95% CI: 43.5-49.8) (P < 0.001). However, the two tests give nearly identical findings in those 5 years and under (N = 94) with a 98% agreement between the tests. Retesting populations with modern assays is necessary to establish better population-level estimates of disease burden.

Global elimination of mother-to-child transmission of hepatitis B: revisiting the current strategy

Mother-to-child transmission (MTCT) of hepatitis B virus (HBV) is a major route of HBV transmission worldwide despite an existing immunoprophylaxis regimen. The implementation of immunoprophylaxis has been challenging, especially in low-income and middle-income countries, where MTCT is common, because of difficulty obtaining and delivering the monovalent HBV vaccine and the HBV immunoglobulin. Global control of the HBV epidemic will need improved prevention of MTCT. We discuss research gaps that hinder development of new options for the elimination of MTCT as well as policy changes that may help the current vaccine-based strategy to live up to its full potential. We propose that decreasing hepatitis B viral concentrations before delivery, along with HBV vaccine use, could provide an alternative strategy that would decrease MTCT of HBV.

Hepatitis E virus seroprevalence in three hyperendemic areas: Nepal, Bangladesh and southwest France

BACKGROUND

Hepatitis E causes a significant burden of disease in developing countries and has recently been increasingly recognized in developed countries. Comparing population anti-hepatitis E virus (HEV) seroprevalence across populations has been difficult.

OBJECTIVES

The aim of this study was to compare the anti-HEV IgG seroprevalence in both adults and children in three hyper-endemic areas (Nepal, Bangladesh and southwest France) using a sensitive, commercial anti-HEV IgG assay.

STUDY DESIGN

Serum or plasma from adults and children in Nepal (n=498), Bangladesh (n=1,009) and Southwest France (n=1031) were tested for anti-HEV IgG using the Wantai assay.

RESULTS

After age-standardization, anti-HEV IgG seroprevalence was 47.1%, 49.8% and 34.0% in Nepal, Bangladesh and southwest France, respectively. There was no difference in seroprevalence by gender in any of the countries. A paucity of infections in children 1-10 years-old was consistently observed (less than 15%) at all 3 locations.

CONCLUSIONS

Surprisingly similar high rates of anti-HEV antibodies were detected using a common, sensitive assay. Despite differences in the epidemiology and circulating genotype of HEV in Nepal, Bangladesh and southwest France, this study found more similarities in population seroprevalence than expected.

Hepatitis e vaccine to prevent morbidity and mortality during epidemics

Recurrent, large, waterborne epidemics of hepatitis E virus (HEV) occur regularly after monsoon rains contaminate water supplies in Asia or during humanitarian crises in Africa. These epidemics commonly affect thousands of persons, and it has a high mortality in pregnant women who become infected. Although a subunit HEV vaccine has been developed by Chinese investigators and was found to be highly effective and safe in a large clinical trial, this vaccine is only available in China. Until it is prequalified by the World Health Organization, the vaccine may not be available for use outside of China in low-income countries that lack national vaccine regulatory agencies. In this manuscript, we explore possible strategies for providing access to this potentially important vaccine for international use in responding to epidemics of HEV in low-resource countries.

A systematic review of the epidemiology of hepatitis E virus in Africa

BACKGROUND

Hepatitis E Virus (HEV) infection is a newly recognized serious threat to global public health and Africa is suspected to be among the most severely affected regions in the world. Understanding HEV epidemiology in Africa will expedite the implementation of evidence-based control policies aimed at preventing the spread of HEV including policies for the use of available resources such as HEV vaccines.

METHODS

Here we present a comprehensive review of HEV epidemiology in Africa based on published data. We searched for articles on HEV epidemiology in Africa from online databases such as PubMed, Scopus, and ISI Web of Science and critically reviewed appropriate publications to extract consistent findings, identify knowledge gaps, and suggest future studies.

RESULTS

Taking a particularly high toll in pregnant women and their fetuses, HEV has infected human populations in 28 of 56 African countries. Since 1979, 17 HEV outbreaks have been reported about once every other year from Africa causing a reported 35,300 cases with 650 deaths.

CONCLUSIONS

In Africa, HEV infection is not new, is widespread, and the number of reported outbreaks are likely a significant underestimate. The authors suggest that this is a continent-wide public health problem that deserves the attention of local, regional and international agencies to implement control policies that can save numerous lives, especially those of pregnant women and their fetuses.

Hepatitis C virus genotypes circulating in patients with chronic hepatitis C in Thailand and their responses to combined PEG-IFN and RBV therapy

Different genotypes of hepatitis C virus (HCV) are circulating in different areas of the world. In Thailand, distribution of HCV genotypes has been investigated mostly in the central area while the information in other regions is limited. This study aimed to determine the HCV genotypes circulating in chronic hepatitis C patients in Chiang Mai, Thailand and to investigate the response of different HCV genotypes to pegylated interferon (PEG-IFN) and ribavirin (RBV) treatment. Patients infected chronically with HCV were treated with PEG-IFN/RBV based on the standard regimens for each HCV genotype and followed up the patients until the end of treatment and 6 months afterward. Out of 158 patients, three major HCV genotypes and eight subtypes were identified. Genotype 3 was the most predominant at 54.5%, followed by genotypes 1 (31%) and 6 (14.5%). Among subtypes, 3a was the most prevalent subtype (45%), followed by 1b (18.4%), 1a and 6f (each at 12.6%), 3b (9.5%), and 6a, 6i, 6n (each at 0.63%). Patients with genotype 3 showed higher rate of responding to the treatment at 80.2% compared to genotypes 1 (73.5%) and 6f (65%). Additionally, patients with genotype 6f showed higher rate of relapsing (25%) compared to genotypes 1 and 3 (14.3% and 16.3%, respectively). In conclusion, this study reported multiple HCV genotypes circulated in Thai patients and the response of different HCV genotypes to PEG-IFN/RBV treatment.

Changes in HIV incidence among people who inject drugs in Taiwan following introduction of a harm reduction program: a study of two cohorts

BACKGROUND

Harm reduction strategies for combating HIV epidemics among people who inject drugs (PWID) have been implemented in several countries. However, large-scale studies using sensitive measurements of HIV incidence and intervention exposures in defined cohorts are rare. The aim of this study was to determine the association between harm reduction programs and HIV incidence among PWID.

METHODS AND FINDINGS

The study included two populations. For 3,851 PWID who entered prison between 2004 and 2010 and tested HIV positive upon incarceration, we tested their sera using a BED HIV-1 capture enzyme immunoassay to estimate HIV incidence. Also, we enrolled in a prospective study a cohort of 4,357 individuals who were released from prison via an amnesty on July 16, 2007. We followed them with interviews at intervals of 6-12 mo and by linking several databases. A total of 2,473 participants who were HIV negative in January 2006 had interviews between then and 2010 to evaluate the association between use of harm reduction programs and HIV incidence. We used survival methods with attendance at methadone clinics as a time-varying covariate to measure the association with HIV incidence. We used a Poisson regression model and calculated the HIV incidence rate to evaluate the association between needle/syringe program use and HIV incidence. Among the population of PWID who were imprisoned, the implementation of comprehensive harm reduction programs and a lower mean community HIV viral load were associated with a reduced HIV incidence among PWID. The HIV incidence in this population of PWID decreased from 18.2% in 2005 to 0.3% in 2010. In an individual-level analysis of the amnesty cohort, attendance at methadone clinics was associated with a significantly lower HIV incidence (adjusted hazard ratio: 0.20, 95% CI: 0.06-0.67), and frequent users of needle/syringe program services had lower HIV incidence (0% in high NSP users, 0.5% in non NSP users). In addition, no HIV seroconversions were detected among prison inmates.

CONCLUSIONS

Although our data are affected by participation bias, they strongly suggest that comprehensive harm- reduction services and free treatment were associated with reversal of a rapidly emerging epidemic of HIV among PWID. Please see later in the article for the Editors' Summary.

Fetal and neonatal health consequences of vertically transmitted hepatitis E virus infection

Hepatitis E virus (HEV) infections lead to tens of thousands of deaths annually, mostly in developing countries. Hepatitis E poses a significant threat to the health of expectant mothers, a well-noted epidemiologic feature of the disease, but the contribution of vertically transmitted HEV infection to fetal and neonatal morbidity and mortality has received limited attention. Evidence assembled to date suggests that mother-to-child HEV transmission may be frequent and deleterious to the fetus and newborn in pregnancies affected by hepatitis E. Additional work is required to resolve key questions. (1) What risks do subclinical maternal HEV infections and infections early in pregnancy pose to fetal health and development? (2) Does vertical transmission occur during labor and/or breastfeeding and contribute appreciably to neonatal morbidity and mortality? (3) How do treatment decisions for severely ill mothers affect fetal and neonatal outcomes? (4) Can maternal vaccination effectively prevent vertical transmission of HEV?

Host immune status and response to hepatitis E virus infection

Hepatitis E virus (HEV), identified over 30 years ago, remains a serious threat to life, health, and productivity in developing countries where access to clean water is limited. Recognition that HEV also circulates as a zoonotic and food-borne pathogen in developed countries is more recent. Even without treatment, most cases of HEV-related acute viral hepatitis (with or without jaundice) resolve within 1 to 2 months. However, HEV sometimes leads to acute liver failure, chronic infection, or extrahepatic symptoms. The mechanisms of pathogenesis appear to be substantially immune mediated. This review covers the epidemiology of HEV infection worldwide, the humoral and cellular immune responses to HEV, and the persistence and protection of antibodies produced in response to both natural infection and vaccines. We focus on the contributions of altered immune states (associated with pregnancy, human immunodeficiency virus [HIV], and immunosuppressive agents used in cancer and transplant medicine) to the elevated risks of chronic infection (in immunosuppressed/immunocompromised patients) and acute liver failure and mortality (among pregnant women). We conclude by discussing outstanding questions about the immune response to HEV and interactions with hormones and comorbid conditions. These questions take on heightened importance now that a vaccine is available.

Hepatitis E virus seroprevalence and molecular study among blood donors in China

BACKGROUND

The risk of hepatitis E virus (HEV) infection from blood transfusion has aroused increasing concern in many countries. The aim of this study was to analyze the potential risk of HEV infection through blood transfusion in China.

STUDY DESIGN AND METHODS

Qualified blood donations and donations with isolated alanine aminotransferase (ALT) elevations from five geographically diverse Chinese regions were tested for anti-HEV immunoglobulin (Ig)M and IgG and HEV antigen. The positive samples for anti-HEV IgM and HEV antigen were tested for HEV RNA. HEV open reading frame (ORF)2 partial sequences were analyzed from HEV RNA-positive samples.

RESULTS

The seroprevalence rates of HEV antigen and anti-HEV IgM and IgG among qualified donations were 0.06% (6/10,741), 1.02% (109/10,741), and 27.42% (2945/10,741), respectively. Samples with isolated ALT elevations had higher prevalence of HEV markers, namely, HEV antigen of 0.25% (2/797), anti-HEV IgM of 2.76% (22/797), and anti-HEV IgG of 40.02% (319/797). The HEV antibody prevalence varied significantly by age, sex, and geographic region. All 131 samples that were anti-HEV IgM positive were negative for HEV RNA, whereas four of eight (50%) samples positive for HEV antigen were HEV RNA positive. HEV ORF2 sequences from three of four HEV RNA-positive samples were determined and grouped with Genotype 4.

CONCLUSION

Qualified donations after routine blood donor screening still carry potential risk for transmitting HEV. HEV antigen screening could be one measure to reduce the risk of HEV transmission by blood transfusion.

Screening utility, local perceptions, and care-seeking for reported jaundeesh among respondents lacking signs of icterus in rural Bangladesh

In rural Bangladesh, acute viral hepatitis presents a significant burden on the public-health system. As part of the formative work for a large epidemiologic study of hepatitis E in rural Bangladesh, we sought to identify local terms that could be used for population-based screening of acute viral hepatitis. Exploration of the local term jaundeesh for screening utility identified a high burden of reported jaundeesh among individuals without symptoms of icterus. Recognizing that local perceptions of illness may differ from biomedical definitions of disease, we also sought to characterize the perceived aetiology, care-seeking patterns, diagnostic symptoms, and treatments for reported jaundeesh in the absence of icteric symptoms to inform future population-based studies on reported morbidities. We conducted a cross-sectional survey among 1,441 randomly-selected subjects to identify the prevalence of reported jaundeesh and to test the validity of this local term to detect signs of icterus. To characterize the perceived aetiology and care-seeking patterns for jaundeesh among the majority of respondents, we conducted in-depth interviews with 100 respondents who self-reported jaundeesh but lacked clinical signs of icterus. To describe diagnostic symptoms and treatments, in-depth interviews were also performed with 25 kabirajs or traditional faith healers commonly visited for jaundeesh. Of the 1,441 randomly-selected participants, one-fourth (n=361) reported jaundeesh, with only a third (n=122) reporting yellow eyes or skin, representative of icterus; Jaundeesh had a positive predictive value of 34% for detection of yellow eyes or skin. Anicteric patients with reported jaundeesh perceived their illnesses to result from humoral imbalances, most commonly treated by amulets, ritual handwashing, and bathing with herbal medicines. Jaundeesh patients primarily sought folk and spiritual remedies from informal care providers, with only 19% visiting allopathic care providers. Although the local term jaundeesh appeared to have limited epidemiologic utility to screen for acute symptomatic viral hepatitis, this term described a syndrome perceived to occur frequently in this population. Future population-based studies conducting surveillance for acute hepatitis should use caution in the use and interpretation of self-reported jaundeesh. Further study of jaundeesh may provide insight into the appropriate public-health response to this syndrome.

A cross-sectional study of hepatitis E virus infection in pigs in different-sized farms in northern Thailand

Pigs are an important reservoir of hepatitis E virus (HEV) in many countries throughout the world. We evaluated the association between farm size and presence of serum antibodies against HEV, as well as other risk factors for infection in pigs raised in Nan Province, Thailand in a cross-sectional study. The sampling frame was a total-population census of all pig herds, stratified into three classes of the farm size according to criteria developed by the Nan provincial livestock health office. One-eighth of all pigs in each farm were sampled randomly. All pig-farm owners were interviewed to elicit information on general characteristics of their farms, biosecurity and hygienic procedures, and farm management. We obtained sera and fecal samples from 879 pigs to test for antibodies to HEV and HEV RNA. Odds ratios (OR) and 95% confidence intervals (CI) for risk factors for HEV seroprevalence were estimated by multivariate logistic regression. The overall prevalence of anti-HEV immunoglobulin G antibodies was 9.9%. Pigs studied from medium-sized farms had a higher HEV seroprevalence than those from larger farms (adjusted OR 4.95, 95% CI: 1.79, 13.70). Factors associated with HEV seropositivity included feeding pigs with agro-industrial byproducts, having veterinarians on farms, and presence of other pig farms within 100 m. Twenty-five (2.9%) of 875 sampled pig stools were positive for HEV RNA. Phylogenetic analysis revealed that all HEV isolates clustered to HEV genotype 3.

An exploratory case control study of risk factors for hepatitis E in rural Bangladesh

Hepatitis E virus (HEV) is the major cause of epidemic and sporadic hepatitis globally. Outbreaks are associated with fecal contamination of drinking water, yet the environmental reservoir of HEV between epidemics remains unclear. In contrast to neighboring countries, where epidemics and sporadic disease co-occur, HEV-endemic communities in rural Bangladesh seldom report outbreaks; sporadic hepatitis E is reported from urban and rural areas of the country. Besides typical enteric risk factors, other routes for HEV infection and disease are unclear. We conducted monthly household surveillance of a southern Bangladeshi community of 23,500 people to find incident cases of acute hepatitis E over a 22 month period. An algorithm was used to capture 279 candidate cases, of which 46 were confirmed acute HEV infections. An exploratory case-control study was conducted to identify putative risk factors for disease. Nearly 70% of cases were over 15 years old. Female gender seemed protective (OR:0.34) against hepatitis E in this conservative setting, as was the use of sanitary latrines (OR:0.28). Socioeconomic status or animal exposures were not significant predictors of disease, although outdoor employment and recent urban travel were. Unexpectedly, recent contact with a “jaundiced” patient and a history of injection exposure in the 3 months prior to disease (OR:15.50) were significant. Susceptible individuals from “endemic” communities share similar enteric exposure risks to those commonly associated with tourists from non-endemic countries. This study also raises the novel possibility of parenteral and person-to-person transmission of HEV in non-epidemic, sporadic disease settings.

Syphilis among men who have sex with men (MSM) in Taiwan: its association with HIV prevalence, awareness of HIV status, and use of antiretroviral therapy

To understand how awareness of HIV-positivity and the use of antiretroviral therapy associated with syphilis infection, 361 MSM attending 16 Hong-Pa (drug-and-sex parties) in Taiwan were studied. The syphilis rate of individuals within their first 2 years after HIV diagnosis (awareness) was lower than that in individuals who had not been diagnosed HIV infection prior to Hong-Pa (unawareness) (Adj OR = 0.24, P < 0.05). Notably, there was a decrease in the beneficial effect of HIV-positive status awareness on syphilis prevention with an increase in time since notification. Moreover, antiretroviral therapy was not associated with a lower incidence of syphilis, and syphilis infection peaked during the treatment dropout period. In conclusion, the duration of a protective effect of knowing one's HIV-positivity against syphilis infection was short, and the highest risk of syphilis infection was observed when patients discontinued antiretroviral therapy. Future research should examine the behavioral mechanisms involved in this prevention failure.

Environmental predictors and incubation period of AIDS-associated penicillium marneffei infection in Ho Chi Minh City, Vietnam

BACKGROUND

Penicillium marneffei is an emerging dimorphic mycosis endemic in Southeast Asia, and a leading cause of mortality among human immunodeficiency virus (HIV)-infected people in the region. Factors governing the seasonal incidence of P. marneffei infection are unknown, and may yield critical insights into possible reservoirs or modes of acquisition.

METHODS

This study included HIV-infected patients presenting with P. marneffei (n = 719) and Cryptococcus neoformans (n = 1598) infection to the Hospital for Tropical Diseases in Ho Chi Minh City, Vietnam, from 2004 to 2010, and temperature, humidity, wind, precipitation, and HIV-related admissions data for the corresponding period. We used multivariate regression modeling to identify factors associated with P. marneffei and C. neoformans admissions. We estimated the P. marneffei incubation period by considering profile likelihoods for different exposure-to-admission delays.

RESULTS

We found that P. marneffei admissions were strongly associated with humidity (P < .001), and that precipitation, temperature, and wind did not add explanatory power. Cryptococcus neoformans admissions were not seasonal, and P. marneffei admissions were more common relative to C. neoformans admissions during months of high (≥85%) humidity (odds ratio, 1.49; 95% confidence interval [CI], 1.10-2.01). Maximum likelihood estimation suggested a P. marneffei incubation period of 1 week (95% CI, 0-3 weeks).

CONCLUSIONS

Our findings suggest that humidity is the most important environmental predictor of P. marneffei admissions, and may drive exposure by facilitating fungal growth or spore release in the environment. In addition, it appears that a high proportion of penicilliosis patients present to the hospital with primary disseminated infection within 3 weeks of exposure.