Clinical Significance

Assay results, in conjunction with other laboratory results and clinical information, may be used to provide presumptive evidence of infection with hepatitis A virus in persons with signs and symptoms of hepatitis and in persons at risk for hepatitis A infection. 

The hepatitis A virus is an RNA‑containing virus that lacks an envelope. It belongs to the family of picornaviruses. To date, just one human serotype and 7 genotypes have been described. The viral capsid consists of 3 proteins (VP1‑VP3) that form an immunodominant structure on the surface of the viral particle that is highly conserved between all genotypes. After vaccination or natural infection, the immune response is directed against this structure. 

Hepatitis A is the most common form of acute viral hepatitis. It is transmitted by the fecal-oral route. The disease has not been known to take a chronic course, nor does the virus persist in the organism. An acute or recently acquired hepatitis A infection can be assumed if anti‑HAV IgM antibodies are detected. Anti‑HAV IgM antibodies can always be detected at the onset of the disease, and usually disappear 3 to 4 months later. Anti‑HAV IgM can also be detected in some patients for a longer period, however. HAV IgM antibodies develop only very rarely after vaccination.

_{Source: Roche Cobas Elecsys Anti-HAV IgM Method Sheet V5.0 11-2022}