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Cytomegalovirus (CMV) Antibody Screening, Serum

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

This test checks for antibodies to the cytomegalovirus (CMV), a common virus that can affect anyone but is especially important for pregnant individuals, people with weakened immune systems, or those undergoing organ transplants.

Quick summary

["Screening for CMV antibodies helps determine if your body has ever been exposed to the virus."]

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

Key facts at a glance

LOINC
31797-4
Short code
CMV Ag Spec Ql
Synonyms
CMV Ag Spec Ql
Category
chemistry
Sample
serum
Container
Red-top tube (SST)
Units
N/A
Fasting
false
Population
adult
Sex
all
Age range
18–65 years
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?

This test detects specific antibodies (immunoglobulins) in your serum that your immune system produces in response to CMV infection. Antibodies are proteins your body makes to fight off viruses. If you have these antibodies, it suggests you’ve either had a past infection or were exposed to CMV.

Why Might You Need This Test?

Doctors may order this test if you have symptoms like fatigue, fever, or swollen lymph nodes, especially if you’re at higher risk for CMV complications (e.g., during pregnancy, after organ transplant, or if you have HIV/AIDS). It’s also used to monitor people who’ve already been exposed to CMV.

What to Expect Before the Test

No special preparation is needed. You’ll have a small needle inserted into your arm to draw a blood sample. The process takes a few minutes, and you may feel a brief pinch. If you’re pregnant or have a weak immune system, let your doctor know before the test.

What to Expect After the Test

After the blood draw, you can resume normal activities. There may be mild bruising or soreness at the site, but this usually goes away quickly. If you experience excessive bleeding or pain, contact your healthcare provider.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

◆Associated findings1

Short name

CMV Antibody Screen

Frequently asked questions

How long does it take to get my test results?
Results are typically available within 1 to 3 business days, depending on your lab. Your doctor will contact you with the final report once it’s ready.
What does a positive result mean for me?
A positive result means your body has detected CMV antibodies, suggesting you’ve been exposed to the virus at some point. This doesn’t necessarily mean you had symptoms, but it’s important for your doctor to assess your risk and next steps, especially if you’re pregnant, immunocompromised, or undergoing treatment.
Can I get CMV if I have a negative test result?
Yes, a negative test result means your body hasn’t produced detectable antibodies yet, but it doesn’t guarantee you’re completely protected. CMV can still infect you later, especially if you’re in a high-risk group. Your doctor may recommend additional testing or monitoring if needed.
  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