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Risk Analysis : An Official Publication... May 2022A quantitative risk assessment of hepatitis A virus (HAV) and hepatitis E virus (HEV) from raw oyster consumption from farm and retail was evaluated over three seasons....
A quantitative risk assessment of hepatitis A virus (HAV) and hepatitis E virus (HEV) from raw oyster consumption from farm and retail was evaluated over three seasons. This risk assessment comprises four steps: hazard identification, dose-response assessment, exposure assessment, and risk characterization. We used probabilistic models for prevalence, concentration, and oyster consumption. HEV dose-response (DR) model based on HEV dosing in chimpanzees and used to perform a dose-response assessment of HEV was proposed. Both HAV and HEV were simultaneously enumerated by real-time PCR to determine viral doses. The probabilistic prevalences of HAV and HEV were in the ranges of 8-20% and 8-40%, respectively. The best-fit DR model was the beta-Poisson with alpha and N equal to 216.9 and 3.03 × 10 , respectively. After running the Monte Carlo simulation, the annual cases of foodborne hepatitis A and hepatitis E from raw oyster consumption from farms were 9,264-17,526 and 1-604, respectively, while those at retail were 7,694-14,591 and 1-204, respectively. This study suggested that consuming farm oysters poses a significantly higher risk of hepatitis A than hepatitis E. The best-fit DR model for HEV developed in this study could determine risks of hepatitis E from raw oyster consumption in Thailand.
Topics: Animals; Hepatitis A; Hepatitis A virus; Hepatitis E; Hepatitis E virus; Ostreidae; Risk Assessment
PubMed: 34601752
DOI: 10.1111/risa.13832 -
Euro Surveillance : Bulletin Europeen... Feb 2021IntroductionUniversal vaccination of toddlers has led to very low hepatitis A (HAV) endemicity in Israel. However, sporadic outbreaks still occur, necessitating better...
IntroductionUniversal vaccination of toddlers has led to very low hepatitis A (HAV) endemicity in Israel. However, sporadic outbreaks still occur, necessitating better surveillance.AimTo implement a comprehensive HAV surveillance programme.MethodsIn 2017 and 2018, sera from suspected HAV cases that tested positive for anti-HAV IgM antibodies were transferred to the Central Virology Laboratory (CVL) for molecular confirmation and genotyping. Sewage samples were collected in Israel and Palestine* and were molecularly analysed. All molecular (CVL), epidemiological (District Health Offices and Epidemiological Division) and clinical (treating physicians) data were combined and concordantly assessed.ResultsOverall, 146 cases (78 in 2017 and 68 in 2018, median age 34 years, 102 male) and 240 sewage samples were studied. Most cases (96%) were unvaccinated. In 2017, 89% of cases were male, 45% of whom were men who have sex with men (MSM). In 2018, 49% were male, but only 3% of them were MSM (p < 0.01). In 2017, 82% of cases and 63% of sewage samples were genotype 1A, phylogenetically associated with a global MSM-HAV outbreak. In 2018, 80% of cases and 71% of sewage samples were genotype 1B, related to the endemic strain previously identified in Israel and Palestine*. Environmental analysis revealed clustering of sewage and cases' sequences, and country-wide circulation of HAV.ConclusionsMolecular confirmation of HAV infection in cases and analysis of environmental samples, combined with clinical and epidemiological investigation, may improve HAV surveillance. Sequence-based typing of both clinical and sewage-derived samples could assist in understanding viral circulation.
Topics: Adult; Disease Outbreaks; Female; Hepatitis A; Hepatitis A virus; Homosexuality, Male; Humans; Israel; Male; Phylogeny; Sexual and Gender Minorities
PubMed: 33573709
DOI: 10.2807/1560-7917.ES.2021.26.6.2000001 -
Journal of Viral Hepatitis Apr 2015Viral hepatitis claims one million lives each year. Scaling up treatment for hepatitis B and C in resource-limited settings is not possible without access to reliable... (Review)
Review
Viral hepatitis claims one million lives each year. Scaling up treatment for hepatitis B and C in resource-limited settings is not possible without access to reliable diagnostic tools. This article gives an overview of current technologies and the pipeline for easy-to-use assays for serological and virological analyses, which can be performed at the site of patient care ('point-of-care assays'). Furthermore, the utility of dried blood spots for hepatitis B and C viral load testing is discussed. In addition to simple and reliable diagnostics, there is a need for a sustainable funding scheme and generic production of antiviral drugs to reduce the burden of viral hepatitis worldwide.
Topics: Diagnostic Tests, Routine; Hepatitis B; Humans; Point-of-Care Systems; Serology; Viral Load; Virology
PubMed: 25762459
DOI: 10.1111/jvh.12385 -
The American Journal of Tropical... Oct 2018Hepatitis A and hepatitis E viruses (HAV and HEV) are the most common etiologies of viral hepatitis in India. To better understand the epidemiology of these infections,...
Hepatitis A and hepatitis E viruses (HAV and HEV) are the most common etiologies of viral hepatitis in India. To better understand the epidemiology of these infections, laboratory surveillance data generated during 2014-2017, by a network of 51 virology laboratories, were analyzed. Among 24,000 patients tested for both HAV and HEV, 3,017 (12.6%) tested positive for HAV, 3,865 (16.1%) for HEV, and 320 (1.3%) for both HAV and HEV. Most (74.6%) HAV patients were aged ≤ 19 years, whereas 76.9% of HEV patients were aged ≥ 20 years. These laboratories diagnosed 12 HAV and 31 HEV clusters, highlighting the need for provision of safe drinking water and improvements in sanitation. Further expansion of the laboratory network and continued surveillance will provide data necessary for informed decision-making regarding introduction of hepatitis-A vaccine into the immunization program.
Topics: Adolescent; Adult; Aged; Child; Child, Preschool; Coinfection; Drinking Water; Enzyme-Linked Immunosorbent Assay; Epidemiological Monitoring; Female; Hepatitis A; Hepatitis A virus; Hepatitis Antibodies; Hepatitis E; Hepatitis E virus; Humans; Immunoglobulin M; India; Male; Middle Aged; Prevalence; Sanitation
PubMed: 30182922
DOI: 10.4269/ajtmh.18-0232 -
World Journal of Gastroenterology May 2017Hepatitis A virus (HAV) is one of the most common infectious etiologies of acute hepatitis worldwide. The virus is known to be transmitted fecal-orally, resulting in... (Review)
Review
Hepatitis A virus (HAV) is one of the most common infectious etiologies of acute hepatitis worldwide. The virus is known to be transmitted fecal-orally, resulting in symptoms ranging from asymptomatic infection to fulminant hepatitis. HAV can also be transmitted through oral-anal sex. Residents from regions of low endemicity for HAV infection often remain susceptible in their adulthood. Therefore, clustered HAV infections or outbreaks of acute hepatitis A among men who have sex with men and injecting drug users have been reported in countries of low endemicity for HAV infection. The duration of HAV viremia and stool shedding of HAV may be longer in human immunodeficiency virus (HIV)-positive individuals compared to HIV-negative individuals with acute hepatitis A. Current guidelines recommend HAV vaccination for individuals with increased risks of exposure to HAV (such as from injecting drug use, oral-anal sex, travel to or residence in endemic areas, frequent clotting factor or blood transfusions) or with increased risks of fulminant disease (such as those with chronic hepatitis). The seroconversion rates following the recommended standard adult dosing schedule (2 doses of HAVRIX 1440 U or VAQTA 50 U administered 6-12 mo apart) are lower among HIV-positive individuals compared to HIV-negative individuals. While the response rates may be augmented by adding a booster dose at week 4 sandwiched between the first dose and the 6-mo dose, the need of booster vaccination remain less clear among HIV-positive individuals who have lost anti-HAV antibodies.
Topics: Adult; Comorbidity; Disease Outbreaks; Female; HIV Infections; HIV Seropositivity; Hepatitis A; Hepatitis A Antibodies; Hepatitis A Vaccines; Hepatitis A virus; Homosexuality, Male; Humans; Immunization Programs; Immunization, Secondary; Immunosuppressive Agents; Male; Seroepidemiologic Studies; Vaccination; Young Adult
PubMed: 28611512
DOI: 10.3748/wjg.v23.i20.3589 -
Viruses May 2020Hepatitis A virus (HAV) infection is one of the major causes of acute hepatitis, and this infection occasionally causes acute liver failure. HAV infection is associated... (Review)
Review
Hepatitis A virus (HAV) infection is one of the major causes of acute hepatitis, and this infection occasionally causes acute liver failure. HAV infection is associated with HAV-contaminated food and water as well as sexual transmission among men who have sex with men. Although an HAV vaccine has been developed, outbreaks of hepatitis A and life-threatening severe HAV infections are still observed worldwide. Therefore, an improved HAV vaccine and anti-HAV drugs for severe hepatitis A should be developed. Here, we reviewed cell culture systems for HAV infection, and other issues. This review may help with improving the HAV vaccine and developing anti-HAV drugs.
Topics: Animals; Antiviral Agents; Cell Culture Techniques; Drug Evaluation, Preclinical; Hepatitis A; Hepatitis A virus; Humans; Viral Vaccines
PubMed: 32408660
DOI: 10.3390/v12050533 -
Journal of Hepatology Sep 2023Hepatitis A virus (HAV) infections are considered not to trigger innate immunity in vivo, in contrast to hepatitis C virus (HCV). This lack of induction has been...
BACKGROUND & AIMS
Hepatitis A virus (HAV) infections are considered not to trigger innate immunity in vivo, in contrast to hepatitis C virus (HCV). This lack of induction has been imputed to strong interference by HAV proteases 3CD and 3ABC. We aimed to elucidate the mechanisms of immune activation and counteraction by HAV and HCV in vivo and in vitro.
METHODS
Albumin-urokinase-type plasminogen activator/severe combined immunodeficiency (Alb/uPA-SCID) mice with humanised livers were infected with HAV and HCV. Hepatic cell culture models were used to assess HAV and HCV sensing by Toll-like receptor 3 and retinoic acid-inducible gene I/melanoma differentiation-associated protein 5 (RIG-I/MDA5), respectively. Cleavage of the adaptor proteins TIR-domain-containing adapter-inducing interferon-β (TRIF) and mitochondrial antiviral-signalling protein (MAVS) was analysed by transient and stable expression of HAV and HCV proteases and virus infection.
RESULTS
We detected similar levels of interferon-stimulated gene induction in hepatocytes of HAV- and HCV-infected mice with humanised liver. In cell culture, HAV induced interferon-stimulated genes exclusively upon MDA5 sensing and depended on LGP2 (laboratory of genetics and physiology 2). TRIF and MAVS were only partially cleaved by HAV 3ABC and 3CD, not sufficiently to abrogate signalling. In contrast, HCV NS3-4A efficiently degraded MAVS, as previously reported, whereas TRIF cleavage was not detected.
CONCLUSIONS
HAV induces an innate immune response in hepatocytes via MDA5/LGP2, with limited control of both pathways by proteolytic cleavage. HCV activates Toll-like receptor 3 and lacks TRIF cleavage, suggesting that this pathway mainly contributes to HCV-induced antiviral responses in hepatocytes. Our results shed new light on the induction of innate immunity and counteraction by HAV and HCV.
IMPACT AND IMPLICATIONS
Understanding the mechanisms that determine the differential outcomes of HAV and HCV infections is crucial for the development of effective therapies. Our study provides insights into the interplay between these viruses and the host innate immune response in vitro and in vivo, shedding light on previously controversial or only partially investigated aspects. This knowledge could tailor the development of new strategies to combat HCV persistence, as well as improve our understanding of the factors underlying successful HAV clearance.
Topics: Hepatitis A virus; Hepatitis A; Hepacivirus; Hepatitis C; Animals; Mice; Immune Evasion; Immunity, Innate; Mice, SCID
PubMed: 37121436
DOI: 10.1016/j.jhep.2023.04.023 -
Tropical Doctor Jan 2023Viral hepatitis is a major public health problem affecting children globally. Clinical presentation varies from asymptomatic illness to hepatitis, and liver failure....
Viral hepatitis is a major public health problem affecting children globally. Clinical presentation varies from asymptomatic illness to hepatitis, and liver failure. Data on clinical features and laboratory parameters were collected and analysed on 300 children, aged 1-12 years, admitted with confirmed viral hepatitis. A small majority (52%) were boys. The mean age of presentation was 6.9 ± 2.8 years with the commonest symptoms being anorexia or vomiting (in 98%), fever (in 89%) and jaundice (in 71.3%). Tender hepatomegaly was seen in 31.7%. Almost all (97.6%) had hepatitis A, though mixed infection (A & E) was seen in 1.7%. Only 8% had serum bilirubin levels >200 µmol/L. Significantly elevated (>20 μkat/L) levels of aspartate transaminase and alanine transaminase were seen in 19% and 25.3% of cases respectively. Coagulopathy (PT >15 s) was present in 11.0% cases. HAV remains the most common cause of viral hepatitis in children in our environment. Public awareness and universal vaccination should be the focus to prevent morbidity and mortality due to these pathogens.
Topics: Male; Child; Humans; Child, Preschool; Female; Child, Hospitalized; Hepatitis, Viral, Human; Hepatitis A; Jaundice; India
PubMed: 35880293
DOI: 10.1177/00494755221105629 -
International Journal of Infectious... Mar 2018Hepatitis A is a viral liver disease whose prevalence is associated with low socio-economic and hygiene levels due to its faecal-oral transmission. Severity increases... (Review)
Review
OBJECTIVES
Hepatitis A is a viral liver disease whose prevalence is associated with low socio-economic and hygiene levels due to its faecal-oral transmission. Severity increases with age, and immunity is life-long. Decreased endemicity could result in increased age and severity of cases. A literature review was conducted to describe changes in age-stratified hepatitis A seroprevalence in Asia Pacific countries from 1980 to 2016, and to identify gaps in the literature. The PRISMA guidelines were followed.
METHODS
The PubMed database was searched for studies on age-specific hepatitis A seroprevalence in 17 Asia Pacific countries. All studies published in the English language, reporting human hepatitis A seroprevalence levels in any age group, were included.
RESULTS
Seventy-three publications from 11 countries were identified. A trend of increasing age at first exposure over time was observed, particularly in developed countries such as Japan, Taiwan, Thailand, and Korea, suggesting a transition in terms of endemicity.
CONCLUSIONS
Extensive gaps in the literature were identified between countries and year of publication, indicating the need for further research. Decreasing hepatitis A exposure and thus immunity conferred during childhood, may render older populations susceptible to infection. The public health and economic value of vaccination against hepatitis A should be assessed within this changing epidemiological context.
Topics: Hepatitis A; Humans; Japan; Meta-Analysis as Topic; Prevalence; Republic of Korea; Seroepidemiologic Studies; Taiwan; Thailand; Vaccination
PubMed: 29292043
DOI: 10.1016/j.ijid.2017.12.021 -
The Brazilian Journal of Infectious... 2023Environmental surveillance of water sources is important to monitoring viral hepatitis transmission in clinical settings. This study investigated the circulation of...
Environmental surveillance of water sources is important to monitoring viral hepatitis transmission in clinical settings. This study investigated the circulation of hepatitis A (HAV) and E (HEV) viruses in sewage and clinical samples from Argentina. Between 2016 and 2017, 80 raw sewage samples and 86 clinical samples (stool and serum) from suspected cases of hepatitis A and hepatitis E were obtained. HAV and HEV were tested by both real-time and nested PCR. Positive samples were sequenced for genotype determination and phylogenetic analysis. Overall, HAV was recovered in 39% of sewage samples and 61.1% of clinical samples. HEV was detected in 22.5% of sewage samples and 15.9% of clinical samples. HAV was found more frequently in sewage during the winter and in clinical samples in spring; HEV was more prevalent in sewage during summer and in clinical samples in autumn. All HAV isolates belonged to genotype IA and HEV isolates belonged to genotype 3, the most prevalent genotypes in South America. High prevalence of HAV and HEV in environmental and clinical samples in Mendoza, Argentina was observed. These findings reinforce the importance of environmental surveillance and implementation of health strategies to control the spread of HAV and HEV in developing countries.
Topics: Humans; Hepatitis A; Hepatitis E virus; Sewage; Argentina; Prevalence; Phylogeny; Hepatitis E; Hepatitis A virus
PubMed: 36603828
DOI: 10.1016/j.bjid.2022.102738