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Serum Anti-Human Immunodeficiency Virus (HIV) Antibody Screening by Immunoassay

Published: August 9, 2026Updated: August 16, 2026

This test detects antibodies to the human immunodeficiency virus (HIV), which your body produces in response to infection. It helps determine if you’ve been exposed to HIV.

Quick summary

["HIV antibody screening is a critical first step in diagnosing potential HIV infection."]

Medically reviewed by WellAlly Editorial TeamLast reviewed August 16, 2026Editorial policy

Key facts at a glance

LOINC
5191-2
Short code
HBV e Ag Ser IA-aCnc
Synonyms
HBV e Ag Ser IA-aCnc
Category
chemistry
Sample
serum
Container
Red-top tube (SST)
Units
N/A
Fasting
false
Population
adult
Sex
all
Age range
18–65 years
Method
ia
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 This Test Measures

The test looks for specific antibodies in your serum that your immune system creates when it encounters HIV. These antibodies are part of your body’s natural defense against the virus. The presence of these antibodies suggests past or current exposure to HIV.

How the Test Works

This test uses an immunoassay method, which detects antibodies in your blood by identifying their interaction with HIV proteins. The result is typically reported as either positive or negative, indicating whether antibodies were found.

Why It’s Done

Doctors may order this test if you have symptoms of HIV, such as fever, fatigue, or unexplained weight loss, or if you’ve had risk factors for infection (e.g., unprotected sex, shared needles, or exposure to HIV). It’s also part of routine testing for people at higher risk.

What to Expect Before the Test

No special preparation is needed. You’ll provide a blood sample from a vein, usually in a doctor’s office or lab. The process is quick and typically painless, though you may feel a slight pinch.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

◆Associated findings1

Short name

HIV Antibody Screen (Serum)

Frequently asked questions

How soon can I get results?
Results are usually available within 24 to 72 hours, depending on the lab. Your healthcare provider will discuss the results with you and explain next steps, such as further testing if needed.
What does a positive result mean?
A positive result means your blood test detected antibodies to HIV, which suggests you may have been infected. This does not confirm the current status of your immune system or the severity of infection. You’ll need additional testing, like a viral load test, to assess whether HIV is actively reproducing in your body.
Can I still be infected if my test is negative?
Yes, it’s possible. HIV antibodies may take weeks to months to develop after exposure. If you suspect you’ve been exposed, ask your doctor about repeat testing or other diagnostic tests, such as a viral load test, which can detect HIV earlier than antibody tests.
  1. 1
    MedlinePlus — Laboratory TestsSource
  2. 2
    Lab Tests OnlineSource
  3. 3
    Mayo Clinic — Tests & ProceduresSource

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.

Medical Disclaimer

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