Coxsackievirus B2 Neutralizing Antibody Test (2nd Specimen)
This blood test measures neutralizing antibodies against Coxsackievirus B2, a common virus that can infect the heart and cause inflammation of the heart muscle or its outer lining. It is often ordered as a follow-up sample to help your doctor determine whether a Coxsackievirus B2 infection is recent, past, or ongoing.
{"The test detects antibodies your body makes to fight Coxsackievirus B2","It helps diagnose heart infections like myocarditis caused by viruses","A second specimen is collected to compare antibody levels over time","Results show whether you have a current or past infection","The test uses a neutralization assay to measure protective antibodies"}
Key facts at a glance
- LOINC
- 24184-4
- Short code
- CVB2 NT
- Synonyms
- CV B2 NAb sp2 Titr Ser Nt
- Category
- cardiac
- Sample
- serum
- Container
- Serum separator tube (SST, gold top) or red top plain tube
- Units
- N/A
- Ref low
- 8
- Ref high
- 64
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- ≥ 0 years
- Method
- Virus neutralization test (plaque reduction neutralization test - PRNT)
- CPT
- 86622
- SNOMED
- 122441009
- Specimen volume
- 1.0-2.0 mL serum minimum
- Stability
- Store at 2-8°C if testing within 7 days. For longer storage, freeze at -20°C or below. Avoid repeated freeze-thaw cycles.
- Hemolysis max
- 50
- Lipemia max
- 100
- Icterus max
- 20
- TAT
- 72–336 hours
- Order
- routine
What is this test?
The Coxsackievirus B2 Neutralizing Antibody test is a blood test that detects and measures specific antibodies (called neutralizing antibodies) your immune system produces in response to Coxsackievirus B2 infection. Neutralizing antibodies are special proteins that can block or 'neutralize' the virus from infecting cells. This test uses a laboratory method called a neutralization assay, which is considered the gold standard for detecting protective immunity against viruses.
Why is it ordered?
This test is primarily ordered when your doctor suspects a viral infection affecting the heart, such as myocarditis (inflammation of the heart muscle) or pericarditis (inflammation of the heart's outer lining). Coxsackievirus B is one of the most common viral causes of heart infections. The '2nd specimen' in the test name means this is a follow-up test—your doctor will compare it to an earlier sample to see if antibody levels are rising, falling, or remaining stable, which helps determine if the infection is recent, past, or ongoing.
How is the test performed?
A healthcare professional will draw a blood sample from a vein in your arm. The blood is collected in a tube, allowed to clot, and then the serum (the liquid part of blood without cells) is separated. The serum is then tested in a laboratory using a neutralization test, which mixes your serum with live virus to see if antibodies in your blood can prevent the virus from infecting cells. The results are reported as a titer—a measure of how much antibody is present.
What do the results mean?
Results are typically reported as a titer (for example, 1:4, 1:8, 1:64). A fourfold increase in antibody titer between the first and second specimen indicates a recent or active infection. A single high titer may suggest a recent infection, while lower, stable titers may indicate a past infection. Your doctor will interpret these results in the context of your symptoms, physical exam, and other test results such as ECG or echocardiogram.
Are there any risks?
The risks are minimal and similar to any standard blood test. You may experience slight pain, bruising, or dizziness at the injection site. In rare cases, infection or excessive bleeding may occur. These tests are generally very safe.
Reference range
Negative: <1:8; Equivocal: 1:8 to 1:32; Positive: ≥1:64. Fourfold rise in titer between acute and convalescent specimens (≥4-fold increase) indicates recent or acute infection. Reference range may vary by laboratory.N/A
No special preparation required. This is a second specimen (convalescent phase) typically collected 2-4 weeks after the acute specimen for seroconversion or titer rise assessment.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
◆Associated findings1
Frequently asked questions
Do I need to fast before this test?
How long does it take to get results?
What are the symptoms of Coxsackievirus B infection?
Is Coxsackievirus B2 contagious?
Can this test tell if I'm immune?
Sources
- 1
- 2
- 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 10, 2026. · Read our editorial policy