The Hepatitis A virus (HAV) is a non-enveloped, single-stranded RNA virus. It is of the Hepatovirus genus and the Picornaviridae family of viruses. There are three genotypes of HAV but they can all be detected with one antibody (making HAV a one serotype virus). HAV is stable under normal environmental conditions and thus can contaminate food or water. It is spread through the fecal-oral route.
According to the CDC, the incidence rate of hepatitis A increased during 2016–2019 due to widespread person-to-person outbreaks, primarily among people experiencing homelessness. Increases in hepatitis A in the past few years has also been reported among men who have sex with men. During 2016–2018, approximately 15,000 hepatitis A cases were reported to the CDC, representing a 294% increase compared with 2013–2015. In 2019, the number of hepatitis A cases reported to CDC peaked at 18,846 cases.
