Severe manifestation of acute hepatitis A recently found in Gunma, Japan

Recent advances in hepatitis A virus research and clinical practice guidelines for hepatitis A virus infection in Japan

In 2018, there was a hepatitis A outbreak in Japan, and hepatitis A virus (HAV) infection is considered a sexually transmitted disease. In general, patients with hepatitis A should be given attention, and this disease should be prevented more than ever. The Japan Agency for Medical Research and Development (AMED) Hepatitis A and E viruses (HAV and HEV) Study Group has worked on the project to create "Recent Advances in Hepatitis A Virus (HAV) Research and Clinical Practice Guidelines for HAV Infection in Japan". The group consists of expert hepatologists and virologists who gathered at virtual meeting on August 5, 2023. Data about the pathogenesis, infection routes, diagnosis, complications, several factors for the severities, vaccination, and current and future treatments for hepatitis A were discussed and debated for a draft version. The participants assessed the quality of cited studies. The finalized recommendations are presented in this review. The recent advances in HAV research and clinical practice for HAV infection in Japan, have been reviewed by the AMED HAV and HEV Study Group.

[Extra hepatic manifestations of hepatitis A]

Viral hepatitis A is characterized by a wide range of clinical pictures ranging from a completely unapparent infection to a fulminant, potentially fatal hepatitis or the classical icteric form. Hepatitis A can develop in an unusual way and extrahepatic manifestations (neurological, renal, haematological, cholecystitis, acute pancreatitis, vasculitis, etc.) can occasionally complicate the course of the disease. Although hepatitis A infection was identified in the early 1970s, there are few or no studies assessing the actual frequency of these complications. They have been studied mainly through clinical case reports. Currently, since the disease has become more common in adults, these complications are being increasingly observed. We present an update on extrahepatic complications during hepatitis A, which should be known by both specialist doctors (infectiologists internists, hepatologists and others) and general practitioners.

[Hepatitis A immunity in refugees in Germany during the current exodus]

BACKGROUND

Germany is facing a huge humanitarian challenge with rapidly rising numbers of refugees entering the country. Data on hepatitis A seroprevalence and infection in refugees and asylum seekers in Europe during the current refugee exodus is scarce.

OBJECTIVES

To assess hepatitis A (HAV) seroprevalence and immunity in refugees arriving in northern Germany in 2015.

MATERIALS AND METHODS

A cross-sectional study of 235 refugees seeking shelter in reception centers in Northern Germany in August 2015 was performed, as acute Hepatitis A had been detected in one refugee in this camp. In order to analyze acute HAV infection and overall immunity, serological screening for HAV antibodies (combined IgG and IgM) was performed. The immunity threshold was defined as <20 IU/l. In all positive screening results, separate IgM testing was performed to detect acute infections.

RESULTS

Males accounted for 84.3 % of HAV screened refugees and the mean age of refugees was 29.1 ± 11.2 years. Children and adolescents below the age of 18 years made up 8.8 % of the migrants. Overall HAV immunity within the cohort was 90 %, and a mild age-dependent increase in HAV immunity was observed, with 81.1 % immunity in children <18 years and a 100 % seropositivity in subjects >50 years. One 20-year-old female refugee had positive IgM results with high HAV antibodies, most likely due to subacute HAV infection.

CONCLUSIONS

This comparably high rate of HAV protected refugees in our cohort supports the notion that the probability of large HAV outbreaks in current German refugee centers is low. However, depending on their current living situation, HAV vaccination should be considered for each refugee child, and healthcare providers and personnel working in refugee centers should be vaccinated against HAV.

Hepatitis A virus detection in food: current and future prospects

Hepatitis A virus (HAV) is responsible for around half of the total number of hepatitis infections diagnosed worldwide. HAV infection is mainly propagated via the faecal-oral route and as a consequence of globalisation, transnational outbreaks of foodborne infections are reported with increasing frequency. Molecular procedures are now available and should be employed for the direct surveillance of HAV in food and environmental samples.

Detection and differentiation of human hepatitis A strains by commercial quantitative real-time RT-PCR tests

Performance characteristics of two commercial quantitative Hepatitis A virus (HAV) RT-PCR assays, the LightCycler Hepatitis A virus quantification kit (Roche Diagnostics) and the RealArt HAV LC RT PCR kit (artus GmbH) for detection and quantification of HAV were evaluated. Both assays rely on reverse transcription and amplification of extracted RNA. Dilutions of two HAV strains, belonging to different subtypes, were prepared to determine the precision, accuracy, linearity and the detection limit. Both assays were found to be suitable for quantification measurement of HAV RNA, but only the Roche kit was able to distinguish the different HAV strains tested. The linear range for the artus assay was 10(4)-10(6)IU/ml and 2 x 10(4) to 2 x 10(8) RNA copies/ml for the Roche assay. The detection limit of Roche kit was 2 TCID(50)/ml or 500 RNA copies/ml and 5 TCID(50)/ml or 50 IU/ml for the artus kit. Despite these small differences it is concluded that both assays are very suitable for detection and quantification of most prevalent HAV subtypes.