HEPATITIS A VIRUS IGG (HAV IGG), SERUM

Hepatitis A Virus IgG (HAV IgG), Serum

What it is

The Hepatitis A Virus IgG (HAV IgG) test is a blood test that detects IgG antibodies against the hepatitis A virus. IgG antibodies develop after recovery from an acute infection or following vaccination. Their presence indicates long-term immunity and protection against hepatitis A. Unlike IgM antibodies, which signify recent or acute infection, IgG reflects past exposure or successful immunization.

Uses

This test is used to:

• Determine immunity to hepatitis A after natural infection or vaccination.
• Differentiate between recent (IgM) and past (IgG) HAV infection.
• Assess the need for vaccination in individuals at risk of exposure.
• Support epidemiological studies and public health monitoring of HAV immunity.

Symptoms That May Lead to the Test

HAV IgG testing is usually performed not for diagnosing acute hepatitis A, but to check immunity status. It may be ordered for people who are at high risk (travelers to endemic areas, healthcare workers, food handlers, or household contacts of infected individuals) or to confirm past exposure. Symptoms of hepatitis A that may lead to broader HAV testing (usually IgM) include jaundice, fatigue, abdominal pain, nausea, vomiting, dark urine, and pale stools.

Abnormal Results

Positive HAV IgG: Indicates past infection or successful vaccination. The individual is immune and protected from reinfection.

Negative HAV IgG: Suggests no evidence of prior infection or vaccination. The individual may be susceptible and may benefit from vaccination if at risk.

Risks

The test requires a standard blood sample. Risks are minimal and may include mild bruising, slight pain, or temporary dizziness at the puncture site, which usually resolve quickly.