Hepatitis A virus IgM (HAV- IgM)

A positive hepatitis A IgM means you have a recent or current hepatitis A infection. IgM antibodies appear soon after exposure and indicate active, often contagious disease; they typically persist for several months. This result differs from IgG, which indicates past infection or immunity. Follow-up includes medical assessment, supportive care, and public‑health steps (notify contacts and consider vaccination or immunoglobulin for exposed, susceptible people).

A positive hepatitis A test means infection or immunity depending on which antibody is detected. IgM-positive indicates acute or recent infection and may cause fever, fatigue, nausea, abdominal pain and jaundice. IgG-positive indicates past infection or vaccination and immunity. Acute hepatitis A is usually self-limiting; treatment is supportive (rest, fluids, avoid alcohol and hepatotoxic drugs). Close contacts may need vaccine or immunoglobulin; cases are reportable.

Hepatitis A is usually an acute, self-limiting infection causing flu-like symptoms and jaundice; most people recover fully within weeks to months. Serious complications are uncommon but can include prolonged illness, hospitalization, or rarely acute liver failure—risk rises with older age and preexisting liver disease. Overall mortality is low (well under 1% for most age groups), and prevention by vaccination and good hygiene is effective.

HAV IgM indicates recent or acute hepatitis A infection: it appears within weeks of exposure, peaks early, and usually disappears after a few months. HAV IgG appears later and indicates past infection or successful vaccination; it persists long-term and confers immunity. Clinically, IgM diagnoses current infection, while IgG shows prior exposure or protective immunity.

Hepatitis A usually causes an acute, self-limited liver infection; most people recover completely with no chronic liver damage. However, it can cause substantial liver inflammation and, rarely—particularly in older adults or those with pre-existing liver disease—lead to acute liver failure, hospitalization, or the need for liver transplantation. Chronic hepatitis A does not occur.

Not necessarily. A positive IgM often indicates recent or acute infection or recent vaccination, but it can reflect false positives or cross‑reactivity. Interpretation depends on symptoms, timing, and other tests such as IgG or PCR. Your clinician may repeat serology, perform confirmatory testing, or evaluate clinical signs. Discuss results with a healthcare provider to determine appropriate follow‑up.