Hepatitis A virus seroprevalence by age and world region, 1990 and 2005

Hepatitis A vaccine immunogenicity 25 years after vaccination in Alaska

The hepatitis A vaccine is recommended for all children greater than or equal to 1 year of age, however, the duration of vaccine protection is unknown and protection through adulthood is crucial to prevent symptomatic hepatitis later in life. We report on 25 years of follow-up of a cohort of Alaska Native individuals who were vaccinated in early childhood. We assessed the duration of vaccine protection by calculating the geometric mean concentration and proportion of participants with protective levels of IgG antibody to hepatitis A virus (anti-HAV) (≥20 mIU/mL) every 2 to 3 years. We estimated the amount of time until the anti-HAV dropped below protective levels using survival analyses. At 25 years, 43 of the original 144 participants were available, mean anti-HAV levels were 91.5 mIU/mL, and 35 (81.4%) had protective levels of anti-HAV. Using data from all persons and all time points, a survival analysis estimated 78.7% of participants had protective levels of anti-HAV at 25 years. The high level of protective antibodies in this cohort indicate that supplemental doses of hepatitis A vaccine are not needed 25 years after completion of the vaccine series.

An outbreak of hepatitis E in Yavatmal, India, 2019

Hepatitis E, a public health concern in developing countries, frequently presents in epidemic, as well as in sporadic forms. This study investigated an outbreak of viral hepatitis at Yavatmal, Maharashtra, India in March 2019. Blood samples from 10 patients were received at Indian Council of Medical Research-National Institute of Virology, Pune to test for the presence of enterically transmitted hepatitis viruses. Subsequently, 49 suspected cases were screened for anti-hepatitis E virus (HEV)/hepatitis A virus (HAV) immunoglobulin M and immunoglobulin G (IgG) antibodies, alanine amino-transferase levels and HEV RNA. Water samples were screened for HEV and HAV RNA followed by phylogenetic analysis. Overall 32 of 49 (65.3%) suspected cases had recent acute HEV infection, while dual infection with HAV was noted in one case (2.04%). Forty-eight of 49 suspected cases were positive for anti-HAV IgG antibodies indicative of previously acquired immunity against HAV. Water samples had evidence of HEV contamination as detected by reverse transcription-polymerase chain reaction. Sequencing of HEV RNA from both patients (n = 2) and water samples (n = 5) indicated HEV genotype 1 to be the etiological agent of this outbreak. Serological and molecular evidence confirmed HEV as the etiology. Mixing of contaminated drain water with the domestic water supply may have triggered this outbreak. Subsequent changing of the defaulted water pipelines and its segregation from drain pipelines by the health authorities resulted in progressive decline of this outbreak. Despite the limitations, periodic surveillance of HEV exposure pattern and reporting of small outbreaks would supplement to the global disease burden data of hepatitis E.

Seroprevalence of hepatitis A virus infection in Central-West of Tunisia

Hepatitis A infections still represent a major global health concern. During the past years, a transition pattern of the hepatitis A epidemiology was noted in many parts of the world. In Tunisia, there is not a recent survey on age-specific hepatitis A virus seroprevalence. This study aimed to investigate the seroprevalence of hepatitis A virus infection in Central-West Tunisia, representative of regions with lowest socioeconomic level in the country, before vaccine implementation. Sera obtained from the blood samples of subjects were screened for the detection of hepatitis A virus. The seroprevalence was evaluated by detection of total antibodies to hepatitis A virus using commercially available immunoassay kits. A total of 1379 subjects, aged 5-75 years (mean age: 29.0 ± 17.3 years) were studied. The global anti-hepatitis A virus seroplevalence was 84.7% (95% confidence interval: [82.6-86.5]). A higher hepatitis A virus seroprevalence was showed in subjects aged 10-14 years compared to those aged less than 10 years (50.0% vs. 31.0%). In subjects aged 20-29 years, a rapid increase in the hepatitis A virus prevalence was noted; it reached 97.0%. The seroprevalence of anti-hepatitis A virus differed by zone of residence (81.1% in rural area vs. 72.4% in urban area, p = .005) and increased significantly with lower level of education (p = .019). There was no statistical significant seroprevalence difference between male and female: 84.2% versus 85.2%, respectively. Our study confirm the transition pattern of the hepatitis A virus endemicity in Tunisia from high to intermediate and provide an evaluation of the hepatitis A virus epidemiological situation before vaccine implementation.

Immunity to hepatitis A virus in liver transplant recipients: A population-based study in Iran

BACKGROUND

Acute hepatitis A is usually a self-limited viral disease but can be severe and even fatal in special groups of patients including those with chronic liver disease and recipients of liver transplantation. To take appropriate preventive measures, it is important to determine the immune status against the hepatitis A virus in patients at risk of grave clinical outcomes following infection. To assess the need for immunization against hepatitis A, we aimed to determine the immune status against hepatitis A in a population of liver transplant recipients. We also investigated the association between hepatitis A immune status and demographic factors such as age and sex, underlying liver disease, source of drinking water, geographical area of residence and socioeconomic status.

METHODS

This cross-sectional study was performed on 242 recipients of allogenic liver transplants at Abu Ali Sina Organ Transplant Hospital in Shiraz, Iran, between January 2017 and April 2017. The level of immunity was assessed using hepatitis A antibody detection kits.

RESULTS

The rate of immunity against hepatitis A was detected as 88.8% in our study population. In the multivariable logistic regression model, younger age (OR=1.175, P<0.001) and higher education level (OR=2.142, P=0.040) were the main determinants of non-immune status. However, hepatitis A immunity was independent of gender, monthly family income, water supply source, residential area and underlying liver disorder.

CONCLUSION

Although a significant proportion of liver transplant recipients in this study showed evidence of natural immunity to hepatitis A, a considerable proportion of younger patients and those with a higher level of education were non-immune. The results of this study signify the importance of screening for hepatitis A immunity in this at-risk population of patients and the need for vaccinating non-immune patients.

Trends in hepatitis A research indexed in the Web of Science: a bibliometric analysis over the period from 1985 to 2019

OBJECTIVE

A bibliometric analysis was conducted to build an all-inclusive view of the status of research on hepatitis A virus (HAV) for facilitating researchers, health professionals, and policymakers to understand the characteristics of research output in this particular domain.

METHODS

A comprehensive search was conducted in the Web of Science database. The obtained data were exported into Microsoft Excel 2019, OriginPro 2018 and VOSviewer software for windows.

RESULTS

From 1985 to 2019, a total of 5,950 studies on HAV were published, with an overall h-index of 105, and 90,350 total citations. The most cited article on HAV was "Classification of chronic viral hepatitis: a need for reassessment" authored by Scheuer in the Journal of Hepatology with a total of 1,121 citations. The most cited article on HAV vaccine was "A controlled trial of a formalin-inactivated hepatitis A vaccine in healthy children" by Werzberger et al. in the New England Journal of Medicine with 401 citations. The most frequent year of publication was 2019 (n = 250). The largest number of studies were funded by the United States Department of Health Human Services (n = 199). The organization with the highest number of publications was the United States Centers for Disease Control and Prevention (n = 228). The United State of America (n = 1,500) was the country with the most publications. 'Vaccine' was the leading journal with 299 publications.

CONCLUSIONS

The highest numbers of studies were published in developed countries. There is a clear need for interdisciplinary research approaches to evaluate and intervene in HAV endemic areas.

Hepatitis A vaccination and its immunological and epidemiological long-term effects - a review of the evidence

Hepatitis A virus (HAV) infections continue to represent a significant disease burden causing approximately 200 million infections, 30 million symptomatic illnesses and 30,000 deaths each year. Effective and safe hepatitis A vaccines have been available since the early 1990s. Initially developed for individual prophylaxis, HAV vaccines are now increasingly used to control hepatitis A in endemic areas. The human enteral HAV is eradicable in principle, however, HAV eradication is currently not being pursued. Inactivated HAV vaccines are safe and, after two doses, elicit seroprotection in healthy children, adolescents, and young adults for an estimated 30-40 years, if not lifelong, with no need for a later second booster. The long-term effects of the single-dose live-attenuated HAV vaccines are less well documented but available data suggest they are safe and provide long-lasting immunity and protection. A universal mass vaccination strategy (UMV) based on two doses of inactivated vaccine is commonly implemented in endemic countries and eliminates clinical hepatitis A disease in toddlers within a few years. Consequently, older age groups also benefit due to the herd protection effects. Single-dose UMV programs have shown promising outcomes but need to be monitored for many more years in order to document an effective immune memory persistence. In non-endemic countries, prevention efforts need to focus on 'new' risk groups, such as men having sex with men, prisoners, the homeless, and families visiting friends and relatives in endemic countries. This narrative review presents the current evidence regarding the immunological and epidemiological long-term effects of the hepatitis A vaccination and finally discusses emerging issues and areas for research.

Prevalence of Hepatitis A Immunity and Decision-tree Analysis Among Men Who Have Sex With Men and Are Living With Human Immunodeficiency Virus in Tokyo

BACKGROUND

Hepatitis A virus (HAV) can be sexually transmitted. However, the level of HAV immunity among patients living with human immunodeficiency virus (HIV) in Japan is unknown. Determining the epidemiology of HAV infections among men who have sex with men (MSM) and who are living with HIV is essential for an HAV vaccination program. This study examined HAV immunity in patients living with HIV and applied the decision-tree analysis to explore the factors of immunoglobulin G (IgG)-hepatitis A (HA) antibodies in MSM living with HIV.

METHODS

We examined the presence of IgG-HA antibodies among patients living with HIV from January to December 2017 in The Hospital of The Institute of Medical Science, The University of Tokyo. We recorded each patient's age, sex, mode of HIV transmission, year of HIV diagnosis, HAV vaccine status, history of HAV infection, and history of other infectious diseases. A decision-tree algorithm was used to reveal the factors and profiles most relevant to the anti-HAV prevalence.

RESULTS

Overall, 378 MSM patients living with HIV were examined for IgG-HA antibodies. After excluding 24 patients who had received a HAV vaccine, the data of 354 MSM were analyzed (median age 45 years, interquartile range 39-51 years). Of the 354 patients, 60 (16.9%) were positive for IgG-HA antibodies. The HA positivity rate increased with patients' age, and age (> 63.5 years) was extracted as the most important variable by classification of the decision-tree algorithm.

CONCLUSIONS

Our study, conducted just before the HAV outbreak among MSM in Tokyo, showed that age was the most relevant factor in anti-HAV prevalences. An extensive HAV vaccination program for MSM patients living with HIV is urgently needed, particularly for younger people.

A comparative volatilomic characterization of Florence fennel from different locations: antiviral prospects

The genus Foeniculum is known for its wide ethnobotanical use in the Mediterranean region. Herein, we explored the compositional differences of volatile oils and headspace aroma of Florence fennel (Foeniculum vulgare var. azoricum (Mill.) Thell.) based on its different organs and various geographical origins via gas chromatography coupled with mass spectrometry (GC-MS). Sixty-seven volatile components were detected with phenylpropenes and monoterpenes, including trans-anethole, limonene, α-pinene, trans-β-ocimene, fenchyl acetate, and fenchone, as major constituents. Phenylpropenes were dominant in fennel hydro-distilled oils, whereas monoterpenes were dominant in most of the headspace aroma. The infraspecific variability was assessed using the unsupervised multivariate data analysis tools PCA and HCA, resulting in segregate clustering of accessions from different organs and locations with trans-anethole, limonene, trans-β-ocimene, fenchone, myristicin, and apiole as major phytomarkers contributing to this segregation. The antiviral activities of samples against hepatitis A and C viruses were investigated using the plaque reduction assay, HAV 3C proteinase and HCV NS5B polymerase inhibitory assays with a percentage inhibition between 66% and 85% and IC50 values from 1.8 to 26.7 μg mL-1. In silico molecular docking scores in latter enzyme binding pockets revealed key allosteric interactions with trans-β-ocimene and β-fenchyl acetate showing the best Gibb's free energy. Florence fennel exhibited interesting new perspectives for medicinal and industrial applications.

Endemicity change of hepatitis A infection necessitates vaccination in food handlers: An Indian perspective

In the last two decades, outbreaks due to the foodborne hepatitis A virus (HAV) have been frequently reported in India, with adolescents and adults primarily affected. In India, most food handlers are adolescents and young adults who might be exposed to unsatisfactory environmental conditions and poor water quality. This increases the risk of HAV infection and consequently compounds the risk of HAV transmission from food handlers to susceptible populations. Given the shift in hepatitis A endemicity from high to intermediate levels in India, implementing the vaccination of food handlers has become important as it can also contribute to the elimination of hepatitis A in India. This narrative review makes a case for hepatitis A immunization of food handlers in India considering the growing food industry, evolving food culture, and the substantial burden caused by hepatitis A outbreaks.

What is the context?

Hepatitis A disease is a common form of viral hepatitis and is transmitted through contaminated food and water or through close contact with an infected person. The virus with stands high temperature and can survive on surfaces for long periods of time.

In India, the burden of hepatitis A has shifted from children to adolescents and adults who are more culnerable to infection. They present a high risk of complications, often requiring hopitalization.

The prevention of the disease has often bee neglected, inadequate safety measures for the preparation of food (via food handlers) is a known risk factor for the transmission of hepatitis A.

What is new?

Our review highlights the relationship between food handling and hepatitis A infection among adolescents and adults in Inida.

The lack of knowledge of food safety regulations and hygiene measures among food handlers and the organizations that guide them may contribute to the spread of hepatitis A.

What is the impact?

Sanitation efforts, awareness and educational programs for food are needed to help reduce the transmission of hepatitis A virus and disease, yet these measures alone may not be sufficient.

Vaccination among high-risk populations such as food handlers can prevent hepatitis A infection and its complications as well as transmission.

[Viral hepatitis A-E]

Hepatitis viruses A-E cause acute and chronic liver inflammation and thus lead to significant morbidity and mortality worldwide. They differ significantly in their biology, course of disease and therapy options. While hepatitis A virus only causes acute infection, hepatitis B can become chronic, even reactivate or occur as coinfection with hepatitis D virus. Whereas these infections are preventable through vaccination, a vaccine does not exist against HCV. However, new direct antiviral agents reliably lead to cure of chronic hepatitis C. Hepatitis E virus frequently causes acute or-in case of immunosuppression-even chronic hepatitis. Continual screening of patients with elevated liver enzymes or risk groups using simple serological markers can enable virus-specific therapy of mostly asymptomatic chronic virus hepatitis, preventing the development of liver cirrhosis and hepatocellular carcinoma.

Hepatotropic viruses: Is Roma population at risk?

Roma people make up a significant ethnic minority in many European countries, with the vast majority living in Central and Eastern Europe. Roma are a vulnerable population group in social, economic, and political terms. Frequent migrations, life in segregated communities, substandard housing, poverty, and limited access to quality health care, including low immunization coverage, affect their health status and predispose them to various diseases, including viral hepatitis. Hepatitis A, B, and E are highly prevalent among Roma and mainly associated with low socioeconomic status. In contrast, hepatitis C does not seem to be more frequent in the Roma population. Enhanced efforts should be directed towards the implementation of screening programs, preventive measures, and treatment of viral hepatitis in Roma communities throughout Europe.

A randomized controlled trial of comparative effectiveness between the 2 dose and 3 dose regimens of hepatitis a vaccine in kidney transplant recipients

Hepatitis A virus (HAV) is able to cause a spectrum of illnesses ranging from no symptom to fulminant hepatitis which may lead to acute kidney injury. Although hepatitis A vaccine is recommended in non-immune solid organ transplant recipients who live in or travel to endemic areas, the standard 2-dose vaccination regimen demonstrated less favorable immunogenicity among these population. The 3-dose regimen showed higher response rate and immune durability in patients with human immunodeficiency virus. However, this strategy has never been studied in solid organ transplant recipients. A single-center, open-labeled, computer-based randomized controlled trial (RCT) with a 2:1 allocation ratio was conducted from August 2017 to December 2018. The study compared the seroconversion rate after receiving 2- or 3-dose regimen of hepatitis A vaccine at 0, 6 and 0, 1, 6 months, respectively, in non-immune kidney transplant recipients. A total of 401 adult kidney transplant recipients were screened for anti-HAV IgG and 285 subjects had positive results so the seroprevalence was 71.1%. Of 116 seronegative recipients, 93 (80.2%) completed vaccination; 60 and 33 participants completed 2- and 3-dose vaccination, respectively. The baseline characteristics were comparable between both groups. The seroconversion rate at 1 month after vaccination was 51.7% in the standard 2-dose regimen and 48.5% in the 3-dose regimen (p = 0.769). Overall, the seroconversion rate appeared to be associated with high estimated glomerular infiltration rate, high serum albumin, and low intensity immunosuppressive regimen. Seroconversion rate after hepatitis A vaccination in kidney transplant recipients was less favorable than healthy population. Three-dose regimen did not show superior benefit over the standard 2-dose regimen. Other strategies of immunization may increase immunogenicity among kidney transplant recipients.

Epidemiologic trends of hepatitis A in different age groups and regions of China from 1990 to 2018: observational population-based study

This study characterises changes in the incidence and mortality of hepatitis A in different age groups and provinces of China from 1990 to 2018, and evaluates the effect of the nation-wide expanded programme on immunisation (EPI). A mathematical model was used to estimate the relative change in incidence and mortality in different provinces and age groups. Interrupted time series regression was applied to evaluate the impacts of the inclusion of vaccination in the EPI during 2007–2018. The geographic clustering of hepatitis A incidence was assessed using global Moran's I and changing trends over time were estimated using joinpoint regression analysis. Both the incidence (odds ratio (OR) for overall relative change: 0.86; 95% confidence interval (CI): 0.85–0.87; P < 0.0001) and the mortality rate (OR for overall relative change: 0.84; 95% CI: 0.83–0.85; P < 0.0001) decreased. Most age groups had significant declines in reported incidence over time. The incidence and mortality of hepatitis A significantly reduced after inclusion of hepatitis A vaccine in EPI, showing that the EPI strategy had a continuous effect on the decreasing trend of hepatitis A burden. Increasing the coverage rate of the vaccine and improving hygiene conditions are the key measures for the control of hepatitis A in China.

Hepatitis A Virus Strains Circulating in the Campania Region (2015-2018) Assessed through Bivalve Biomonitoring and Environmental Surveillance

The genetic diversity of Hepatitis A Virus (HAV) circulating in the Campania Region in years 2015–2018 was investigated through the monitoring of sentinel bivalve shellfish and water matrices. Overall, 463 water samples (71 sewage samples, 353 coastal discharge waters, and 39 seawaters samples), and 746 bivalve shellfish samples were analyzed. Positivity for HAV was detected in 20/71 sewage samples, 14/353 coastal discharge waters, 5/39 seawaters, and 102/746 bivalve shellfish. Sixty-one of the positive samples were successfully sequenced and were characterized as genotype IA (n = 50) and IB (n = 11). The prevalent strain circulating in 2015 in both bivalves and waters was the IA strain responsible for the outbreak occurring around the same time in the Naples area. This variant was no longer identified in subsequent years (2017–2018) when, instead, appeared two of the IA variants of the multistate outbreak affecting men who have sex with men (MSM), VRD_521_2016, and RIVM-HAV16–090, with the former prevailing in both shellfish and water environments. HAV IB isolates were detected over the years in shellfish and in water matrices, but not in clinical samples, suggesting that this genotype had been circulating silently. An integrated surveillance system (environment/food/clinical cases) can be a useful tool to monitor changes in viral variants in the population, as well as an early warning system.

Genetic diversity, haplotype analysis, and risk factor assessment of hepatitis A virus isolates from the West Bank, Palestine during the period between 2014 and 2016

BACKGROUND

Hepatitis A virus (HAV) infection is one of the major causes of acute viral hepatitis. HAV genotypes and its genetic diversity is rarely investigated in our region as well as worldwide.

AIMS

The aims of the present study were to determine the HAV genotypes and its risk factors and to investigate the genetic diversity of the HAV isolates in the West Bank, Palestine.

STUDY DESIGN

A cohort of 161 clinically and laboratory-confirmed HAV (IgM-positive) cases and 170 apparently healthy controls from all the districts of the West Bank, Palestine during the period of 2014 to 2016 were tested for HAV infection using IgM antibodies, RT-PCR and sequence analysis of the VP3/VP1 junction region of the HAV genome. Phylogenetic analysis, genetic diversity and haplotypes analysis were used to characterize the VP3/VP1 sequences.

RESULTS

All the 34 sequences of the HAV were found to be of HAV-IB sub-genotype. The phylogenetic analysis showed four main clusters with cluster III exclusively consisting of 18 Palestinian isolates (18/23-78%), but with weak bootstrap values. A high haplotype diversity (Hd) and low nucleotide diversity (π) were observed. Cluster III showed high number of haplotypes (h = 8), but low haplotype (gene) diversity (Hd = 0.69). A total of 28 active haplotypes with some consisting of more than one sequence were observed using haplotype network analysis. The Palestinian haplotypes are characterized by closely related viral haplotypes with one SNV away from each other which ran parallel to cluster III in the phylogenetic tree. A smaller Palestinian haplotype (4 isolates) was three SNVs away from the major haplotype cluster (n = 10) and closer to others haplotypes from Iran, Spain, and South Africa. Young age, low level of parent's education, infrequent hand washing before meals, and drinking of un-treated water were considered the major HAV risk factors in the present study.

CONCLUSION

Haplotype network analysis revealed haplotype variation among the HAV Palestinian sequences despite low genetic variation and nucleotide diversity. In addition, this study reconfirmed that age and parent's level of education as HAV risk factors, while hand washing and treating drinking water as protective factors.

The excretion rate and stability of HAAg in human fecal samples after live attenuated hepatitis A vaccination

The live attenuated hepatitis A virus vaccine (HA-L) is in routine use in the Chinese national immunization program (NIP). The major disadvantages of HA-L include that theoretically, it may be possible for mutation shifts and secondary infections of the live vaccine viral strain. The aim of this study was to explore variation in the viral strain after vaccination with the HA-L. A total of 1297 fecal samples (including 470 for the 18 to 36-month-old age group, 527 for the 3 to 16-year-old group, and 300 for the 16 years and older group) were collected in the study, and the rate of hepatitis A virus (HAV) positivity in fecal samples was 11.36% (31/273), 11.44% (31/271), 9.70% (26/268), 8.47% (21/248), and 9.70% (23/237) on days 0, 7, 14, 21 and 28, respectively. A total of 77 HAV positive samples were randomly selected for VP1/2A (360 bp, 2218-2577) gene analysis. Phylogenetic trees were then constructed by the neighbor-joining method. Phylogenetic analyses showed that all the isolated HAV strains belonged to sub-genotype IB, which was the same as the vaccine strain. Compared with the vaccine strain, HM-175/7MK-5 (M16632.1), there were only two base mutations discovered, at 2291 and 2568. However, the amino acid mutation analysis showed that those base mutations were synonymous mutations. The isolated HAV strains were genetically stable. This study provides a reference for the safety concern regarding the routine and wide-range use in people older than 18 months.

Hepatitis A antibody persistence 8 and 10 years after 1-dose and 2-dose vaccination in children from Panama

BACKGROUND

Hepatitis A virus (HAV) remains a global public health concern, which is potentially growing in Latin America, due to an expected shift from high to intermediate endemicity levels. The use of HAV vaccines in pediatric national immunization programs (NIPs), either as a 2-dose or a 1-dose schedule, has been explored in Latin American countries; however, evidence demonstrating long-term protection in this population is limited in the region. We evaluated long-term antibody persistence following a 1-dose partial series and the recommended 2-dose schedule used in Panama's pediatric NIP.

METHODS

Two independent cross-sectional serological surveys were conducted at year 8 (Y8) and Y10 following vaccination under the NIP with 1 or 2 doses of an inactivated HAV vaccine (Havrix, GSK). Seropositivity (anti-HAV antibody concentration ≥ 15 mIU/mL) rates and antibody geometric mean concentrations (GMCs) were assessed at each serosurvey. Non-inferiority of 1 dose versus 2 doses was also explored.

RESULTS

This study (NCT02712359) included 600 and 599 children at Y8 and Y10 post-vaccination, respectively. Seropositivity rates were 74.3% (95% confidence interval [CI]: 69.0; 79.2) and 97.7% (95% CI: 95.3; 99.1) at Y8 and 71.9% (95% CI: 66.4; 76.9) and 96.3% (95% CI: 93.5; 98.2) at Y10, in the 1-dose and 2-dose groups, respectively. Antibody GMCs were lower in the 1-dose versus the 2-dose group in both surveys. Non-inferiority was not demonstrated since the lower limit of the 2-sided 95% CI for the between-group difference in seropositivity rates (1-dose minus 2-dose) was < -10%.

CONCLUSION

Anti-HAV antibody persistence was observed in lower percentages of children receiving 1 dose versus 2 doses of Havrix, at 8 and 10 years post-vaccination in Panama. Further investigations are needed to confirm antibody persistence and conclude on the protection afforded beyond 10 years in the pediatric population in Latin America.

Hepatitis A and Hepatitis E: Clinical and Epidemiological Features, Diagnosis, Treatment, and Prevention

Hepatitis A and E are both ancient diseases but have only been properly recognized as being caused by distinct pathogens in modern times. Despite significantly different genomic structures, both viruses employ remarkably similar strategies to avoid host detection and increase environmental transmission. There are millions of cases of acute viral hepatitis due to hepatitis A virus (HAV) and hepatitis E virus (HEV) each year, resulting in tens of thousands of deaths. The presentations can be clinically indistinguishable, but each virus also has a range of less common but more specific phenotypes. The epidemiology of HAV is complex, and is shifting in countries that are making improvements to public health and sanitation. HEV presents a significant public health challenge in resource-limited settings but has historically been incorrectly regarded as having little clinical relevance in industrialized countries.

First evidence for continuous circulation of hepatitis A virus subgenotype IIA in Central Africa

Although a high seroprevalence of antibodies against hepatitis A virus (HAV) has been estimated in Central Africa, the current status of both HAV infections and seroprevalence of anti-HAV antibodies remains unclear due to a paucity of surveillance data available. We conducted a serological survey during 2015-2017 in Gabon, Central Africa, and confirmed a high seroprevalence of anti-HAV antibodies in all age groups. To identify the currently circulating HAV strains and to reveal the epidemiological and genetic characteristics of the virus, we conducted molecular surveillance in a total of 1007 patients presenting febrile illness. Through HAV detection and sequencing, we identified subgenotype IIA (HAV-IIA) infections in the country throughout the year. A significant prevalence trend emerged in the young child population, presenting several infection peaks which appeared to be unrelated to dry or rainy seasons. Whole-genome sequencing and phylogenetic analyses revealed local HAV-IIA evolutionary events in Central Africa, indicating the circulation of HAV-IIA strains of a region-specific lineage. Recombination analysis of complete genome sequences revealed potential recombination events in Gabonese HAV strains. Interestingly, Gabonese HAV-IIA possibly acquired the 5'-untranslated region (5'-UTR) of the rare subgenotype HAV-IIB in recent years, suggesting the present existence of HAV-IIB in Central Africa. These findings indicate a currently stable HAV-IIA circulation in Gabon, with a high risk of infections in children aged under 5 years. Our findings will enhance the understanding of the current status of HAV infections in Central Africa and provide new insight into the molecular epidemiology and evolution of HAV genotype II.

Hepatitis A epidemiology in Latin American countries: a 2020 view from a systematic literature review

INTRODUCTION

The World Health Organization recommends vaccination against hepatitis A virus (HAV) for children aged 1 year and older in areas where endemicity has shifted from high to intermediate. There are no recent comprehensive reviews of the epidemiology of HAV infection in Latin America, but seroprevalence and socioeconomic data suggest that, with improved clean water and sanitation systems, countries are transitioning to intermediate endemicity.

AREAS COVERED

We conducted a systematic literature review of the epidemiology of HAV infection in 25 countries in the Latin American region, which included gray literature. We compiled data on HAV incidence and prevalence, including the identification of epidemiological changes observed in countries that established pediatric HAV vaccination programs.

EXPERT OPINION

We identified 59 relevant articles, including 34 peer-reviewed seroprevalence studies (12 recent studies from Brazil), three incidence studies, and six vaccine impact studies (three from Argentina). Based on the estimated age at midpoint of population immunity in each country, most have a high-intermediate, intermediate, or low-intermediate level of HAV endemicity, suggesting that national childhood immunization may be an appropriate disease prevention strategy. However, recent data were lacking for most countries. Improved data quality and continued epidemiological surveillance are required for this region.

Immunity to Hepatitis-A virus: A nationwide population-based seroprevalence study from Iran

BACKGROUND

The mortality rate of acute Hepatitis A increases from 0.1% in the children to 1.2%, in the adults. Hepatitis A is efficiently prevented by HAV-vaccine, but the strategy for distributing this vaccine among countries is dependent on their level of immunity to HAV. This study aimed to detect the level of immunity to HAV in Iran.

METHODS

In this population-based seroprevalence study, 5419 participants from 12 of provinces of Iran, including 57 urban and 120 rural areas were chosen through a multi-stage cluster random sampling. Participants were interviewed by filling checklists and 3 cc of blood sample was obtained from each of them. IBM SPSS statistics V.21 software was used for univariable and multivariable analysis of data.

RESULTS

Mean of age of Interviewees was 26.4 ± 16 years, ranging from 1 to 94 years with a male to female ratio 1.02. Overall, 3603 (66.5%) of subjects were seropositive for HAV-IgG. Among the age groups, 41.1% of children by the age 15 years and 82.6% of adults around 30 years old were immune to HAV. The Mid-point age of population immunity was 21 years. Residents of the borders of the country, people who had less access to the safe water or sanitary toilet, individuals with low socioeconomic status and persons who were a member of dense families had the most probability of seropositivity.

CONCLUSIONS

This study showed that Iran is among HAV low endemic countries and vaccination against HAV is recommended only in the high-risk population, including patients with chronic liver diseases, patients with coagulopathy, travelers to the high endemic areas, and homosexuals. Establishment of national HAV surveillance system, concerning of health system about the occurrence of the HAV outbreaks, implementation of harm reduction strategies, improving economic indices and sanitation and access to the safe water in the deprived regions is recommended.

Hepatitis a virus infection in Central-West Tunisia: an age structured model of transmission and vaccination impact

BACKGROUND

The epidemiological pattern of hepatitis A infection has shown dynamic changes in many parts of the world due to improved socio-economic conditions and the accumulation of seronegative subjects, which leads to possible outbreaks and increased morbidity rate. In Tunisia, the epidemiological status of hepatits A virus is currently unknown. However, over the past years higher numbers of symptomatic hepatitis A virus infection in school attendants and several outbreaks were reported to the Ministry of Health, especially from regions with the lowest socio-economic levels in the country. The aim of this study was to investigate the current seroprevalence of hepatitis A virus antibodies in central-west Tunisia and assess the impact of hepatitis A virus vaccination on hepatitis A epidemiology.

METHODS

Serum samples from 1379 individuals, aged 5-75 years, were screened for hepatitis A virus antibodies. Adjusted seroprevalence, incidence and force of infection parameters were estimated by a linear age structured SEIR (Susceptible-Exposed-Infectious-Recovered) compartmental model. A vaccine model was then constructed to assess the impact on hepatitis A virus epidemiology of 3 scenarios of vaccination strategies: one dose at 12-months of age, one dose at 6-years and one dose at 12-months and another at 6-years of age during 6 years.

RESULTS

A rapid increase in anti-hepatitis A virus seroprevalence was noted during infancy and adolescence: 47% of subjects under 10-years-old are infected; the prevalence increases to 77% at 15-years and reaches 97% in subjects aged 30-years. The force of infection is highest between 10 and 30-years of age and the incidence declines with increasing age. The vaccine model showed that the 3-scenarios lead to a significant reduction of the fraction of susceptibles. The two doses scenario gives the best results. Single-dose vaccination at 6-years of age provides more rapid decrease of disease burden in school-aged children, as compared to single-dose vaccination at 12-months, but keeps with a non-negligible fraction of susceptibles among children < 6-years.

CONCLUSIONS

Our study confirms the epidemiological switch from high to intermediate endemicity of hepatitis A virus in Tunisia and provides models that may help undertake best decisions in terms of vaccinations strategies.

Hepatitis A, B and C seropositivity among first-year healthcare students in western Turkey: a seroprevalence study

Background

The risk of viral hepatitis among healthcare students (HCSs) is greater than that among the general population. Therefore, this study was conducted to investigate the seroprevalence of the hepatitis A virus (HAV), hepatitis B virus (HBV) and hepatitis C virus (HCV) among first-year HCSs at a university in Turkey and as a secondary objective, to determine the factors associated with HAV and HBV seropositivity.

Methods

This cross-sectional study was performed in first-year HCSs in Izmir, western Turkey. Data were collected using a self-administered questionnaire including items on sociodemographic characteristics, medical history, and hygiene. A total of 650 HCSs were tested for the HAV, HBV and HCV markers. Categorical variables were compared using the chi-square test. The association between independent variables and anti-HAV seropositivity and anti-HBs seropositivity was assessed by multinomial logistic regression analysis.

Results

The overall frequency of total anti-HAV seropositivity was 34.9%. HBsAg, total anti-HBc and anti-HBs seropositivity were found in 0.3, 1.2 and 93.7% of samples, respectively. All of the HCSs were negative for anti-HCV. Total anti-HAV seropositivity was found to be 1.73 times higher in those ≥21 years old, and it was 1.61 times higher in those who perceived their economic status to be average and 2.75 times higher in those who perceived their economic status to be low. Total anti-HAV seropositivity was found to be 4.37 times higher in those who lived in provinces with intermediate human development index levels. Total anti-HBs seropositivity was found to be 2.48 times higher in those ≤20 years old, and it was 2.13 times higher in those who perceived their economic status to be average.

Conclusions

Approximately two out of three HCSs were susceptible to HAV infection. Since HCSs are at high risk for HAV infection, they should be vaccinated before medical clerkships begin. Our results indicate that there is a high prevalence of anti-HBs seropositivity among HCSs. This result may be largely attributed to the implementation of a successful vaccination program in Turkey since 1998.

The Discovery of Hepatitis Viruses: Agents and Disease

Discovery of five hepatitis viruses A to E has followed distinctive definable phases. Human experiments at Willowbrook identified two forms of hepatitis namely infectious hepatitis and serum hepatitis. The discovery of Australia antigen in 1965 led to rapid scientific developments in viral hepatitis. SH antigen was detected in sera of patients with serum hepatitis and soon SH antigen and Australia antigen were found to be identical and selectively associated with serum hepatitis. In 1970, 42-nm Dane particles were detected in Australia antigen positive sera and linked to the virus of serum hepatitis. Subsequently, a new antigen-antibody system (e-antigen/antibody) was detected in such patients and associated with infectivity. Then, DNA polymerase was found in concentrated pellets containing Australia antigen. Hepatitis B virus (HBV) DNA cloning and sequencing of HBV followed these developments. In 1973, 27 nm hepatitis A virus (HAV)-like particles were visualized in stool samples obtained during acute phase of illness after inoculation of MS-1 strain in volunteers. Cloning and sequencing of HAV followed. In 1977, a new antigen-antibody system (δ antigen-antibody system) was identified by chance associated with HBV. Based on animal transmission studies, δ agent was found to be another virus called hepatitis D virus that is defective, requires the helper functions of HBV and interferes with HBV replication. The search for hepatitis C virus started when non-A, non-B hepatitis was recognised in multiply transfused patients with subsequent successful animal transmission. HCV was identified by a novel immunoscreening approach involving screening of cDNA libraries from infectious sera. The story of hepatitis E is historically linked to discovery of waterborne epidemic non-A, non-B hepatitis from Kashmir, India. Virus-like-particles of the agent were identified in stool samples of a human volunteer after a self-experimentation. HEV cDNA was detected in bile-enriched infectious samples and full-length HEV RNA genome was subsequently cloned and sequenced.

Indian National Association for the Study of the Liver Consensus Statement on Acute Liver Failure (Part 1): Epidemiology, Pathogenesis, Presentation and Prognosis

Acute liver failure (ALF) is an infrequent, unpredictable, potentially fatal complication of acute liver injury (ALI) consequent to varied etiologies. Etiologies of ALF as reported in the literature have regional differences, which affects the clinical presentation and natural course. In this part of the consensus article designed to reflect the clinical practices in India, disease burden, epidemiology, clinical presentation, monitoring, and prognostication have been discussed. In India, viral hepatitis is the most frequent cause of ALF, with drug-induced hepatitis due to antituberculosis drugs being the second most frequent cause. The clinical presentation of ALF is characterized by jaundice, coagulopathy, and encephalopathy. It is important to differentiate ALF from other causes of liver failure, including acute on chronic liver failure, subacute liver failure, as well as certain tropical infections which can mimic this presentation. The disease often has a fulminant clinical course with high short-term mortality. Death is usually attributable to cerebral complications, infections, and resultant multiorgan failure. Timely liver transplantation (LT) can change the outcome, and hence, it is vital to provide intensive care to patients until LT can be arranged. It is equally important to assess prognosis to select patients who are suitable for LT. Several prognostic scores have been proposed, and their comparisons show that indigenously developed dynamic scores have an edge over scores described from the Western world. Management of ALF will be described in part 2 of this document.

Hepatitis A Virus in Lao People's Democratic Republic: Seroprevalence and Risk Factors

Despite several recent reports of outbreaks of hepatitis A, little is known about the disease burden in Lao People's Democratic Republic (PDR). We conducted a cross-sectional age-stratified seroprevalence study of anti-hepatitis A virus (HAV) IgG and risk factors in a rural province (Xiengkhouang) and Vientiane capital in Lao PDR. Overall, 62% of participants were anti-HAV positive in Xiengkhouang Province compared with 45.5% in Vientiane capital. In Xiengkhouang, 23.7% of 5- to 10-year-olds were already seropositive compared with 5% in Vientiane. A dramatic increase in seroprevalence occurred between 15- to 20-year and 21- to 30-year age-groups (35.7-62.4%, Xiengkhouang, and 11.5-69.7%, Vientiane) until essentially all older adults were positive in both locations. The main risk factors for HAV antibodies were age, non-Lao-Tai ethnicity, and food-related risk factors. In conclusion, Lao children seem to be exposed very early to HAV, particularly in rural settings, and exposure continues throughout their lives, mostly without being reported. In the older birth cohorts, the high seroprevalence may largely reflect poor sanitation and exposure during childhood. In Vientiane capital, the lower seroprevalence at young ages may reflect better water sanitation since the late 1990s. A comparison with neighboring Thailand indicates that the impact of improved sanitation in Lao PDR began only two decades later. Further improvements in water sanitation, in particular in the rural districts, and better food hygiene are warranted. Our study also suggests that HAV infections are underreported. Improved reporting would provide guidance for targeted interventions to further reduce HAV infections.

Factors associated with anti-hepatitis A virus immunoglobulin G seropositivity among Korean workers: a cross-sectional study

OBJECTIVES

Hepatitis A incidence in Korea has dramatically increased in recent years. Individuals in their twenties and thirties, who account for majority of the workforce in Korea, are particularly susceptible to infection owing to a low seroprevalence of anti-hepatitis A virus (anti-HAV) immunoglobulin G (IgG). This study aimed to identify behavioural and occupational factors related to anti-HAV IgG seropositivity.

DESIGN

Cross-sectional study.

SETTING

A large university hospital in Seoul, Korea.

PARTICIPANTS

Workers in formal employment having an annual routine health screening.

PRIMARY OUTCOME MEASURE

Anti-HAV IgG seropositivity.

RESULTS

Of 131 711 individuals who had an annual health screening at the study hospital in 2018, 68 612 met the inclusion criteria and were included in the analysis. Study participants were predominantly men (64.3%) and in their thirties (55.3%). The overall seroprevalence of anti-HAV IgG was 36.2%. In multivariate analyses, anti-HAV IgG seropositivity was independently associated with working in a workplace with ≥2 health managers (vs no health manager, adjusted OR 1.32, 95% CI 1.22 to 1.43); age 40-49 years (vs 20-29 years, OR 2.51, 95% CI 2.36 to 2.68); female sex (OR 1.54, 95% CI 1.48 to 1.59); experience of any general disease (vs no general disease history, OR 1.19, 95% CI 1.14 to 1.25), obesity (vs normal weight, OR 0.91, 95% CI 0.86 to 0.97); and hepatitis B antibody seropositivity (OR 2.39, 95% CI 2.31 to 2.49).

CONCLUSIONS

The low prevalence of anti-HAV IgG seropositivity points to a need for implementation of workplace-based hepatitis A vaccine programmes. To promote workers' health and prevent hepatitis A outbreaks, occupational health managers, healthcare providers and policy-makers should focus on individuals who are susceptible to HAV, such as young men.

Hepatitis A: Epidemiology, Natural History, Unusual Clinical Manifestations, and Prevention

Hepatitis A virus (HAV) is a positive-strand RNA virus that is transmitted feco-orally through person-to-person contact. Outbreaks are often linked to poor sanitation, overcrowding, or food and water contamination. Infection is often asymptomatic in children, but adults present with jaundice, abdominal pain, hepatitis, and hyperbilirubinemia. Diagnosis is through detection of immunoglobulin M antibodies against HAV, and treatment is supportive. Vaccination is the mainstay of prevention and should be given before exposure whenever possible.

Global Epidemiology of Viral Hepatitis

Viral hepatitis (A, B, C, D, and E) is the leading cause of inflammation of liver tissue (hepatitis). The disease burden associated with hepatitis A and E occurs shortly after infection; it is more severe among adults. With hepatitis A and E, the number of incident cases (new acute infections) is important from a public health perspective. Long-term hepatitis has been shown to cause cirrhosis and hepatocellular carcinoma in patients. The disease burden associated with hepatitis B, C, and D appears 10 to 20 years after infection. Thus, the prevalence of these infections is important from a public health perspective.

In silico designing of peptide based vaccine for Hepatitis viruses using reverse vaccinology approach

Five different Hepatitis virus from different viral species cause viral-hepatitis, which is a life threatening disease leading to a high number of loss of lives every year. The mode of infection and transmission is different for each species and mostly spreads by direct contact and body fluids (for HBV and HCV). No such vaccine is available that can cure all types of Hepatitis with cross-protection. Thus our study involves a peptide based vaccine design with the help of Immunoinformatics approach. We focused only on the secretory and extracellular proteins of each types and identified their epitopes. Epitopes were examined for antigenicity, allergenicity, toxicity, anti-inflammatory property and IFN-γ induction. The short-listed peptides were stitched using linkers and TLR4 adjuvant. This final vaccine was proven to have good physico-chemical and structural properties. Simulation study to determine structural stability of the vaccine showed good result. Docking structure of vaccine with TLR4 has high affinity binding. Immune-simulation reveals favourable induction of immune response with high level of interleukins production important for immunity. Periplasmic expression in E.coli K12 strain was quite satisfactory. This study of designing recombinant chimeric vaccine using reverse vaccinology method provides some idea about the vaccine production against Hepatitis virus.

Origin of HAV strains responsible for 2016-2017 outbreak among MSM: Viral phylodynamics in Lazio region

In Europe HAV infection occurs mainly among specific risk groups, such as consumers of specific food. Sexual transmission of HAV has been demonstrated, particularly among Men-Who-Have-Sex-With-Men (MSM), causing MSM-specific outbreaksin Europe. Here we report a molecular epidemiologic and phylodynamic analysis on HAV sequences in Lazio (central Italy)to identify genetic background and the phylogenetic relations, and test the HAV infection dynamics during a large outbreak through phylodynamic model.Among all HAV sequences found during 2013-2018 in Lazio, low genetic diversity was observed in HAV population in 2016 and 2017, along with high frequenciesVRD_521_2016and RIVM-HAV16-090, suggesting a large expansion event of viral population. The initial expansion of both VRD_521_2016 and RIVM-HAV16-090 clusters dated back to 2012 (95% HPD:2006-2015). During the2016-2017outbreak in Lazio region, the Re peaked around mid-2016, with a value of 1.73 (95% HPD: 1.03-2.37), consistent with incidence trend of AHA cases in Lazio between 2016 and mid-2017. This study showed the magnitude of HAV outbreak in Lazio during 2016-2017, demonstrating the epidemic continuity to MSM-specific outbreak in Europe. The HAV dataset is available on interactive phylodynamic platform https://nextstrain.org to real-time update of future outbreaks.

Sexual behaviour and poor hygiene are related to recent hepatitis a virus community outbreaks

OBJECTIVES

there has been a global increase in the incidence of hepatitis A infection. The aim of this study was to examine the characteristics of the increase in our region and the degree of adherence to the recommended hygienic measures after discharge from hospital.

METHODS

demographic, clinical and biochemical variables were collected from patients with acute hepatitis A in our health area. The patients were grouped as follows: January 2010 to December 2016 (historical cohort) and January 2017 to October 2017 (recent cohort). A phylogenetic analysis was also performed in the recent cohort. One month after discharge, bacterial growth was evaluated by a culture of the dominant hand imprint and were compared with a control group.

RESULTS

a total of 110 cases were registered with a median age of 36.3 years (range 3-89) and 77.3 % were male. The incidence was 0.82/100,000 inhabitants/year and 22.75/100,000 inhabitants/year in the historical and recent cohorts, respectively. Patients in the recent cohort were more frequently male (52.6 % vs. 82.4 %, p = 0.008) and younger (51.7 [3-89] vs. 33.4 [4-74] years, p < 0.001). In addition, 63.8 % of the recent cohort were men who had sex with other men and had unsafe sexual practices (37.5 %). Phylogenetic analysis showed a predominance of genotype A and a high frequency of the VRD 521-2016 sequence. A higher growth of enterobacteria was observed in patients with hepatitis A compared to the control group (7.3 % vs. 1.2 %, p = 0.005), despite specific hygienic measures given at discharge.

CONCLUSIONS

a recent outbreak of hepatitis A in our area was related with gender, younger age and sexual practices. Hepatitis A infected subjects showed a poor adherence to hygienic measures. Our data suggests the need for policies that encourage preventive actions, particularly vaccination in this high-risk group.

Status of adult immunity to hepatitis A virus in healthcare workers from a tertiary care hospital in north India

Background & objectives:

Humans are considered to be the principal host for hepatitis A virus (HAV) infection. In India, heterogeneous groups of susceptible individuals coexist in different regions. There has been a decline in antibody titres to HAV among young adults which may pose a major public health problem. The objective of this study was to assess the IgG anti-HAV level among healthcare workers (HCWs) in the age group of 20-60 yr and its association with the socio-demographic variables.

Methods:

Blood sample (2 ml) was collected under aseptic conditions from each participant followed by the preparation of serum and storing at −20°C. ELISA-based kits were used for the determination of IgG antibodies to HAV in the human serum samples.

Results:

Two hundred and fifty four HCWs were enrolled. IgG anti-HAV antibodies were detected in 97.2 per cent of the samples analyzed. No differences were observed in the levels of IgG anti-HAV antibody and education, income, occupation and socio-economic classes of the HCWs. A seropositivity rate of over 90 per cent was seen amongst all the socio-economic classes.

Interpretation & conclusions:

High levels of IgG protective antibodies were seen among the studied HCWs, hence HAV vaccination may not be required. It will be advisable to do a cost-benefit analysis of vaccination for HAV.

A novel, bedside, etiology specific prognostic model (Peds-HAV) in hepatitis A induced pediatric acute liver failure

BACKGROUND

Hepatitis A virus (HAV) is the commonest cause of pediatric acute liver failure (PALF) in developing countries. Our objective was to develop and validate a HAV-etiology specific prognostic model in PALF.

METHODS

All children with HAV induced PALF (IgM HAV reactive) were included. Outcome was defined at day 28. Only those with death or native liver survival were included. The model (Peds-HAV) was derived using the independent predictors of outcome and validated in a prospective independent cohort.

RESULTS

Hepatitis A accounted for 131 (45.9%) of total 285 PALF. After excluding 11 children who underwent liver transplant, 120 children (74 survivors and 46 death) were included. The first 75 patients formed the derivation cohort and the next 45 patients formed the prospective validation cohort. In the derivation cohort, INR: OR 2.208, (95% CI 1.321-3.690), p = 0.003, grade of hepatic encephalopathy (HE): OR 3.078, (95% CI 1.017-9.312), p = 0.047 and jaundice-to-HE interval: OR 1.171, (95% CI 1.044-1.314), p = 0.007 were independent predictors of death. The final model comprised three criteria: (1) presence of grade 3-4 HE, (2) INR greater than 3.1, and (3) jaundice to HE interval more than 10 days. Presence of 2 or more of these criteria predicted death with 90% sensitivity, 81.4% specificity and 84.9% accuracy. Peds-HAV model was superior to existing prognostic models. In the validation cohort, Peds-HAV model predicted death with 83.3% sensitivity and 92.6% specificity.

CONCLUSION

Peds-HAV model is a simple, bedside, dynamic, etiology (HAV) specific prognostic model based on 3 objective parameters with optimum sensitivity and specificity, hence should be used as liver transplant listing criteria in HAV induced PALF.

Infectious diseases detected by screening after arrival to Denmark in internationally adopted children

AIM

To show the prevalence of selected infectious diseases among internationally adopted children (IAC) in Denmark.

BACKGROUND

Each year approximately 200 IAC arrive in Denmark. These are at increased risk of infectious diseases rarely seen in Danish children. Studies from the 1990s showed that 60% of IAC had infectious diseases and that the majority of these were undetected without screening.

METHODS

The study is a prospective study of medical records from children seen in the adoption clinic at Copenhagen University Hospital in the period 2009-2013. Screening was done for hepatitis A (HAV), B (HBV) and C (HCV), syphilis, HIV, tuberculosis (TB) and intestinal parasites.

RESULTS

In 245 IAC tested, 2% had evidence of recent HAV infection, 3% with HBV and one child with HCV, and no cases of HIV were found. One child had antibodies against syphilis (anti-Trpa AB positivity), and 2% were latently infected with tuberculosis. We found 30% infected with pathogenic intestinal parasites. Only 46% had serologic evidence of immunisation against HBV.

CONCLUSION

The prevalence of infections in IAC was lower than previously reported but compared to the general population, a higher prevalence of intestinal parasites, hepatitis and tuberculosis was found. We recommend that IAC are offered screening shortly after arrival.

Short-term immunogenicity and safety of hepatitis-A and varicella vaccines in HIV-exposed uninfected and HIV-unexposed South African children

BACKGROUND

HIV-exposed uninfected (HEU) children have increased risk of infectious morbidity during early childhood. We evaluated the short-term immunogenicity and safety of single dose inactivated hepatitis-A virus (HAV) vaccine and live attenuated varicella zoster virus (VZV) vaccine in South African children.

METHODS

195 HIV-unexposed and 64 HEU children received either one dose of HAV or VZV vaccine at 18 months of age. Blood samples were tested for hepatitis-A or VZV antibodies before and one month after vaccination by chemiluminescent microparticle immunoassay and enzyme-linked immunosorbent assay, respectively. All children were evaluated for solicited adverse events (AEs).

RESULTS

One-month post-vaccination, a similar percentage of HIV-unexposed (91.8%) and HEU (82.9%) children were seropositive for hepatitis-A (p = 0.144). VZV antibody geometric mean fold-rise was also similar in HIV-unexposed (5.6; 95%CI: 4.6-6.7) and HEU children (5.1; 95%CI: 3.7-7.2); however, only 44% HIV-unexposed and HEU seroconverted (titers > 50 mIU/ml). AEs occurred with similar frequency and severity between groups, except for more systemic AEs after VZV vaccination in HEU than HIV-unexposed children.

CONCLUSIONS

Single dose HAV and VZV vaccine was similarly immunogenic in HIV-unexposed and HEU children. We did not identify differences in short-term humoral immunity after administration of either a live attenuated or inactivated vaccine. Seroconversion rates after a single dose of VZV vaccine were, however, lower compared to reports from previous studies (85-89%).

CLINICAL TRIALS REGISTRATION

NCT03330171.

Environmental and Adaptive Changes Necessitate a Paradigm Shift for Indicators of Fecal Contamination

Changes in the occurrence, distribution, and seasonal variation of waterborne pathogens due to global climate change may increase the risk of human exposure to these microorganisms, thus heightening the need for more reliable surveillance systems. Routine monitoring of drinking water supplies and recreational waters is performed using fecal indicator microorganisms, such as Escherichia coli , Enterococcus spp., and coliphages. However, the presence and numbers of these indicators, especially E. coli and Enterococcus spp., do not correlate well with those of other pathogens, especially enteric viruses, which are a major cause of waterborne outbreaks associated with contaminated water and food, and recreational use of lakes, ponds, rivers, and estuarine waters. For that reason, there is a growing need for a surveillance system that can detect and quantify viral pathogens directly in water sources to reduce transmission of pathogens associated with fecal transmission. In this review, we present an updated overview of relevant waterborne enteric viruses that we believe should be more commonly screened to better evaluate water quality and to determine the safety of water use and reuse and of epidemiological data on viral outbreaks. We also discuss current methodologies that are available to detect and quantify these viruses in water resources. Finally, we highlight challenges associated with virus monitoring. The information presented in this review is intended to aid in the assessment of human health risks due to contact with water sources, especially since current environmental and adaptive changes may be creating the need for a paradigm shift for indicators of fecal contamination.

Nationwide Hospital-Based Seroprevalence of Hepatitis A and Hepatitis E Virus in Bangladesh

Background:

Hepatitis A virus (HAV) and hepatitis E virus (HEV) are transmitted by the fecal-oral route and are responsible for epidemic and sporadic outbreaks of acute hepatitis in low-income countries like Bangladesh.

Objective:

The purpose of this study was to describe the seroprevalence of acute hepatitis due to HAV and HEV infection in Bangladesh.

Methods:

The nationwide food-borne illness surveillance started in 2014 at 10 different hospitals which covered seven divisions of Bangladesh. Blood samples were collected from suspected acute hepatitis cases and screened for the anti-HAV IgM and anti-HEV IgM using enzyme-linked immunosorbent assay (ELISA). Participants’ socioeconomic status, clinical, sanitation and food history were recorded. Multivariate logistic regression was performed to determine the risk factors associated with HAV and HEV infection.

Findings:

A total of 998 patients were enrolled and tested for both HAV and HEV. Among these, 19% (191/998) were identified as HAV positive and 10% (103/998) were HEV positive. The median age was 12 years and 25 years for HAV and HEV positive patients, respectively. The prevalence of HAV was higher among the females (24.9%), whereas HEV was higher among males (11.2%). The highest occurrence of HAV was observed among children while HEV was most prevalent in the 15–60 years age group (12.4%).

Conclusion:

Through our nationwide surveillance, it is evident that hepatitis A and hepatitis E infection is common in Bangladesh. These data will be useful towards planning preventive and control measures by strengthening the sanitation programs and vaccination strategies in Bangladesh.

Immunity to hepatitis A among men who have sex with men attending a large sexual health clinic in Melbourne, Australia, 2012-2018

BACKGROUND

Outbreaks of hepatitis A are being reported more commonly among men who have sex with men (MSM) globally. Australia has also reported a sharp increase in the number of cases of hepatitis A in 2017. This study aimed to determine the level of immunity to hepatitis A among MSM attending a large urban sexual health clinic in Victoria in the lead up to recent outbreak.

METHODS

This was a retrospective audit of serological testing data from first-time MSM attendees at Melbourne Sexual Health Centre (MSHC) in Australia from 1 January 2012 to 31 December 2018. We determined the proportion of MSM who were tested and who had serological detection of hepatitis A IgG, stratified by age and calendar year. We used univariable and multivariable logistic regression to investigate factors associated with testing for and detection of hepatitis A IgG.

RESULTS

There were 16 609 first-time MSM attendees at MSHC over the 7-year period, of which 9718 (59%, 95% CI 58% to 60%) were tested for hepatitis A IgG. There was a 2% annual increase in the proportion of men tested (from 60% in 2012 to 69% in 2018; OR=1.02, 95% CI 1.00 to 1.03, p=0.025). Men born outside of Australia/New Zealand, and younger men <30 years had higher odds of being tested. Of those tested, 44% (n=4304, 95% CI 43% to 45%) had hepatitis A IgG detected at their first visit, with no change over time (OR=1.01, 95% CI 0.99 to 1.03, p=0.210). Detection of hepatitis A IgG was associated with being aged 30 years or older (adjusted OR=2.06, 95% CI 1.89 to 2.24, p<0.001) or being born overseas versus Australia/New Zealand (AOR=1.21, 95% CI 1.11 to 1.31, p<0.001).

CONCLUSION

Hepatitis A immunity among MSM remains below the estimated 70% required to prevent outbreaks. Measures including increased testing and higher vaccination coverage are needed to prevent outbreaks and to limit the number of cases and deaths.

Alginate-coated chitosan nanoparticles act as effective adjuvant for hepatitis A vaccine in mice

The numerous recent hepatitis A outbreaks emphasize the need for vaccination; despite the effectiveness of the current ones, developments are needed to overcome its high cost plus some immune response limitations. Our study aims to evaluate the use of chitosan and alginate-coated chitosan nanoparticles as an adjuvant/carrier for the hepatitis A vaccine (HAV) against the traditional adjuvant alum. Immune responses towards (HAV-Al) with alum, (HAV-Ch) with chitosan, and (HAV-aCNP) with alginate-coated chitosan nanoparticles, were assessed in mice. HAV-aCNP significantly improved the immunogenicity by increasing the seroconversion rate (100%), the hepatitis A antibodies level, and the splenocytes proliferation. Thus, the HAV-aCNP adjuvant was superior to other classes in IFN-γ and IL-10 development. Meanwhile, the solution formula of HAV with chitosan showed comparable humoral and cellular immune responses to alum-adjuvanted suspension with a balanced Th1/Th2 immune pathway. The current study showed the potential of alginate-coated chitosan nanoparticles as an effective carrier for HAV. Consequently, this would impact the cost of HAV production positively.

Quantitative PCR Detection of Enteric Viruses in Wastewater and Environmental Water Sources by the Lisbon Municipality: A Case Study

Current regulations and legislation require critical revision to determine safety for alternative water sources and water reuse as part of the solution to global water crisis. In order to fulfill those demands, Lisbon municipality decided to start water reuse as part of a sustainable hydric resources management, and there was a need to confirm safety and safeguard for public health for its use in this context. For this purpose, a study was designed that included a total of 88 samples collected from drinking, superficial, underground water, and wastewater at three different treatment stages. Quantitative Polimerase Chain Reaction (PCR) detection (qPCR) of enteric viruses Norovirus (NoV) genogroups I (GI) and II (GII) and Hepatitis A (HepA) was performed, and also FIB (E. coli, enterococci and fecal coliforms) concentrations were assessed. HepA virus was only detected in one untreated influent sample, whereas NoV GI/ NoV GI were detected in untreated wastewater (100/100%), secondary treated effluent (47/73%), and tertiary treated effluent (33/20%). Our study proposes that NoV GI and GII should be further studied to provide the support that they may be suitable indicators for water quality monitoring targeting wastewater treatment efficiency, regardless of the level of treatment.

Epidemiology of hepatitis A in Greece in the last decade: management of reported cases and outbreaks and lessons learned

Hepatitis A is a mandatory notifiable disease in Greece. Here, we present the epidemiological data for 2009-2018 and the results of outbreak investigations performed, and discuss future public health priorities.Overall, 1193 cases were reported; 320 migrants/refugees, 240 Roma, 112 travellers and 521 from the general population. The median age of the affected general population (37 years) had an increasing trend (from 30.8 years in 2009 to 40.5 in 2018, P < 0.001) and was significantly higher than that among Roma and migrants (7 and 8 years, respectively, P < 0.001). Twenty-two cases (2.2%) were unvaccinated patients with a chronic liver disease. Fifty clusters with 2-12 cases each were recorded; 44 were attributed to person-to-person transmission and six to food consumption. Three outbreaks accounting for 32.3% of the total number of recorded cases were identified; in 2013 among Roma (112 cases), in 2016 among refugees (188 cases) and in 2017 among men having sex with men (96 cases; 33 of them (34.4%) HIV-positive). The epidemiological data depict that improving living conditions and vaccination coverage of deprived populations, and informing adults on the disease focusing at faecal-oral transmission during sexual intercourse and travel should be the future public health priorities.

The impact of universal live attenuated hepatitis A vaccines in Henan, China, 2005-2018

OBJECTIVES

To analyze the effects of one dose of live attenuated hepatitis A vaccine in a developing country.

METHODS

The reported cases of hepatitis A virus (HAV) infection from 2005 to 2018 in Henan province, China, were analyzed. Data of vaccinated children were assessed on the childhood immunization information management system. Questionnaire survey and blood sample collection were randomly conducted in six counties and districts of Henan province to analyze the prevalence of HAV lgG among the population aged 0-70 years.

RESULTS

In 2008, Henan province began to expand its program on immunization, and children aged 18 months were given one dose of live attenuated hepatitis A vaccine (HepA-L). From 2005 to 2007, the HAV incidence remained steady at above 5000 cases per year and increased to 7489 in 2007. Since 2008, the HAV incidence decreased cumulatively from 4576 to 237 in 2018, indicating a 94.8% decrease, which was particularly pronounced among adolescents (98.2%). The proportion of hepatitis A cases in patients younger than 10 years continually decreased from 41.6% in 2012 to 3.8% in 2018. The reduction of reported cases older than 40 years was slower than that of children. In 2012, the proportion of hepatitis A cases older than 40 years was 27.6%, and continually increased to 69.2% (164/237) in 2018. The results of serological investigation showed that the 0-1.5-year age group had the lowest anti-HAV IgG prevalence (38.6%), which increased to 75.0% in the 4-6-year age group, covered by this immunization program.

CONCLUSIONS

The data indicated a large decrease in HAV infections in Henan province from 2008 onward in response to the introduction of a planned immunization program of HepA-L.

Immunization Against Hepatitis A in Migrant Children: Three Vaccination Strategies, A Retrospective Study

BACKGROUND

Hepatitis A is endemic in many countries. Swiss guidelines recommend vaccinating patients native from endemic areas. In Geneva's Children's hospital, migrant children are screened and vaccinated if seronegative. Because hepatitis A's prevalence is decreasing worldwide, more children are seronegative at arrival, highlighting the need for immunization in medical centers and refugee camps and questioning the benefits of systematic serology. Other Swiss hospitals vaccinate regardless of serostatus. This study's aim is to assess migrant children's immunity according to origin and age, and the cost-effectiveness of different immunization strategies.

METHODS

We retrospectively analyzed 329 children's serostatus (1-16 years of age) between 2012 and 2015, using enzyme-linked fluorescent assay method. Serology and vaccine costs were based on local prices. Groups were compared with χ test and the age-seropositivity relationship was studied with linear regression.

RESULTS

The predominant regions were the Eastern Mediterranean and European Regions with mostly negative serologies (71% and 83%) and the African Region with mostly positive serologies (79%). Immunity varied depending on birth country. Regardless of region, seropositivity increased with age (P < 0.001). The most cost-effective vaccination strategy was an individualized approach based on age and origin, reducing costs by 2% compared with serology-guided immunization and by 17% compared with systematic vaccination.

CONCLUSIONS

Many migrant children >5 years old are seronegative and at risk of clinical infection. They need to be immunized. New guidelines according to age and origin should be defined to reduce immunization costs. We recommend systematic vaccination for patients <5 years old or native from low endemicity areas (≤25.7% of seropositivity). For the others, we propose serology-based vaccination.

High Rates of Exposures to Waterborne Pathogens in Indigenous Communities in the Amazon Region of Ecuador

Waterborne pathogens, associated with poverty and poor sanitary conditions, are a major cause of morbidity and mortality worldwide. There are limited data on the epidemiology of waterborne pathogens in indigenous populations living in the Amazon region. We did a cross-sectional survey in two indigenous Shuar communities in the Amazon region of Ecuador in which we documented the presence of pathogens representing different sources of environmental contamination of water. We detected protozoa and soil-transmitted helminths by microscopy of fecal samples and the presence of IgG antibodies to hepatitis A and Leptospira spp. in blood samples from individuals older than 2 years and collected data by questionnaire on sociodemographic factors and knowledge of infectious diseases. Seroprevalence for hepatitis A and Leptospira spp. were 98.1% (95% CI: 97.0-99.8) and 50.0% (95% CI: 43.3-56.6), respectively, whereas 62.6% (95% CI: 55.8-69.4) had enteric parasites in stool samples. In participants older than 6 years, eight of 10 had evidence of infection with or exposure to at least one of the pathogens studied. Although prevalence of pathogens varied by age, it did not vary significantly by gender, temporal migration, illiteracy, perceived morbidity, receipt of conditional cash transfers, water boiling practices, poor housing conditions, and anthropometric status. These findings indicate a high level of contamination of drinking water by human pathogens in these indigenous communities and the need for interventions to improve access to and use of clean drinking water in these marginalized communities.