Hepatitis A

Hepatitis A is a viral infection caused by hepatitis A virus (HAV), described in the source material as a positive-strand RNA virus ^[1][2]. The disease is characterized as a vaccine-preventable acute inflammatory illness of the liver ^[2]. Source-backed detail on genotype diversity, incubation period, or chronicity beyond the statement that it usually does not leave chronic sequelae is not yet available from the provided snippets ^[2].

The clinical picture is usually acute and self-limited, with the liver inflammation typically resolving spontaneously without chronic sequelae ^[2]. In children, infection is often asymptomatic, whereas adults may present with jaundice, abdominal pain, hepatitis, and hyperbilirubinemia ^[1]. The provided sources note that up to 20% of patients can have a prolonged or relapsed course, and fewer than 1% experience acute liver failure ^[2]. Host factors including immunological status, age, pregnancy, and underlying hepatic disease can influence severity ^[2].

The source material reports that hepatitis A causes more than 150 million new infections annually ^[2]. Outbreaks are often linked to poor sanitation, overcrowding, or contamination of food and water, indicating a strong relationship with environmental and social conditions ^[1]. The available evidence also notes that more than 25 countries have implemented vaccination programmes, with a resulting reduction in incidence ^[2]. Source-backed detail on regional distribution beyond endemicity categories is not yet available from the provided snippets ^[2].

HAV is transmitted feco-orally, and person-to-person contact is explicitly identified as a route of spread ^[1]. The source material also links outbreaks to food and water contamination, poor sanitation, and overcrowding, which are consistent with exposure settings that facilitate fecal-oral transmission ^[1][2]. Source-backed detail on persistence in the environment or specific high-risk exposures is not yet available from the provided snippets.

The supplied sources identify higher risk of severe disease in people with immunological compromise, older age, pregnancy, and underlying hepatic disease ^[2]. The WHO-linked prevention guidance also refers to individuals at higher risk of infection and/or severe disease, particularly in very low, low, and intermediate endemicity settings ^[2]. Source-backed detail on additional exposure-defined groups is not yet available from the provided snippets.

Vaccination is described as the mainstay of prevention and should be given before exposure whenever possible ^[1]. The sources further state that the WHO recommends vaccination for individuals at higher risk of infection and/or severe disease in very low and low endemicity countries, and universal childhood vaccination in intermediate endemicity countries ^[2]. Improving hygiene and sanitation, together with rapid outbreak identification and prompt, accurate intervention, are presented as essential measures for reducing transmission ^[2].

In surveillance terms, hepatitis A should be read as a vaccine-preventable fecal-oral infection whose burden is shaped by sanitation, crowding, and contamination of food and water ^[1][2]. The provided sources indicate that outbreaks can be identified through rapid recognition and control interventions, and that incidence has declined where vaccination programmes have been implemented ^[2]. Source-backed detail on case definitions, laboratory confirmation workflows, or routine reporting thresholds is not yet available from the provided snippets.

1. 1 Abutaleb A et al. Hepatitis A: Epidemiology, Natural History, Unusual Clinical Manifestations, and Prevention. Gastroenterol Clin North Am. 2020 Jun. PMID: 32389358. doi: 10.1016/j.gtc.2020.01.002. PubMed: https://pubmed.ncbi.nlm.nih.gov/32389358/
2. 2 Van Damme P et al. Hepatitis A virus infection. Nat Rev Dis Primers. 2023 Sep 28. PMID: 37770459. doi: 10.1038/s41572-023-00461-2. PubMed: https://pubmed.ncbi.nlm.nih.gov/37770459/
3. 3 Kwo PY et al. ACG Clinical Guideline: Evaluation of Abnormal Liver Chemistries. Am J Gastroenterol. 2017 Jan. PMID: 27995906. doi: 10.1038/ajg.2016.517. PubMed: https://pubmed.ncbi.nlm.nih.gov/27995906/
4. 4 Lupus Hepatitis and Autoimmune Hepatitis (Lupoid Hepatitis). The American Journal of the Medical Sciences. 2017. doi: 10.1016/j.amjms.2016.10.014. DOI: https://doi.org/10.1016/j.amjms.2016.10.014
5. 5 Hepatitis Without Hepatitis? American Journal of Gastroenterology. 2012. doi: 10.1038/ajg.2012.16. DOI: https://doi.org/10.1038/ajg.2012.16
6. 6 Hepatitis Viruses: Hepatitis B and Hepatitis D. Viral Infections of Humans. 2022. doi: 10.1007/978-1-4939-9544-8_32-1. DOI: https://doi.org/10.1007/978-1-4939-9544-8_32-1

ICD-10

B15

ICD-11

1E50.0

Total cases

464K

Total deaths

140

Peak month

2019-01

Coverage

9 reporting countries · 2000-01-01 → 2023-12-30