Anti-Hepatitis A Virus Immunoglobulin M (IgM) Antibody, Serum
This test checks for the presence of IgM antibodies against Hepatitis A virus in your blood. IgM antibodies appear shortly after infection and can help identify recent exposure to the virus.
["IgM antibodies to Hepatitis A can signal an acute infection within days to weeks of exposure."]
Key facts at a glance
- LOINC
- 39300-9
- Short code
- FLUAV H13 Ab Titr Ser HAI
- Synonyms
- FLUAV H13 Ab Titr Ser HAI
- Category
- chemistry
- Sample
- serum
- Container
- Red-top tube (SST)
- Units
- N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- Method
- hai
- Specimen volume
- 5 mL
- Stability
- Room temperature: 4h, Refrigerated: 24h, Frozen: 7d
- Hemolysis max
- 500
- Lipemia max
- 1000
- Icterus max
- 500
- TAT
- 4–24 hours
- Order
- routine
What Does This Test Measure?
The test detects IgM antibodies produced by your immune system in response to Hepatitis A virus infection. These antibodies are typically found in the blood during the early stages of illness, often before symptoms appear or after they start to improve.
Why Might This Test Be Ordered?
Your healthcare provider may order this test if you have symptoms of Hepatitis A (such as fatigue, nausea, abdominal pain, or jaundice) or if you’ve been exposed to someone with Hepatitis A. It can also help confirm a recent infection or diagnose suspected cases in outbreaks.
What to Expect Before the Test
No special preparation is needed for this blood test. You may have a small needle inserted into your arm to draw blood, and you’ll rest briefly afterward. If you’re on blood-thinning medication or have a bleeding disorder, let your provider know.
What to Expect After the Test
After the blood draw, you may feel slight discomfort or bruising at the site. Apply pressure to stop any bleeding, and avoid vigorous activity for a few hours. Most people recover quickly without complications.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
Positive IgM results strongly suggest recent Hepatitis A infection, often within 2–6 weeks of exposure. While IgM levels decline over time, they remain detectable for months to years. This test is critical for diagnosing acute cases, guiding treatment decisions, and preventing spread in communities.
Short name
IgM Anti-HAV
Frequently asked questions
How long does it take to get results from this test?
What does a positive result mean?
Can I still spread Hepatitis A if my test is positive?
Sources
- 1
- 2Lab Tests OnlineSource
- 3
Click any link to access the full source. PubMed Central (PMC) links provide free full-text access.
This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.
This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.
If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.
Medically reviewed by WellAlly Editorial Team Last reviewed August 16, 2026. · Read our editorial policy