Skip to content

Respiratory Syncytial Virus (RSV) Antibody, IgG (Serum) – Quantitative

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

This test measures the amount of Immunoglobulin G (IgG) antibodies against Respiratory Syncytial Virus (RSV) in your blood. IgG antibodies help your immune system recognize and fight RSV, a common virus that can cause respiratory infections.

Quick summary

["IgG antibodies indicate past exposure to RSV and long-term immune protection."]

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

Key facts at a glance

LOINC
5875-0
Short code
RSV Ag Throat Ql IF
Synonyms
RSV Ag Throat Ql IF
Category
chemistry
Sample
serum
Container
Red-top tube (SST)
Units
N/A
Fasting
false
Population
adult
Sex
all
Age range
18–65 years
Method
if
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 the presence of RSV-specific IgG antibodies in your serum. These antibodies develop after your body has encountered RSV, either through infection or vaccination. The result helps determine if you have built immunity to RSV, which can be important for understanding protection against future infections.

Why Might You Need This Test?

Doctors may order this test if you have a history of RSV infections, are at high risk for severe illness (such as infants, elderly adults, or those with weakened immune systems), or if you’re being considered for RSV vaccination. It can also help assess immune response after vaccination.

What to Expect Before the Test

No special preparation is needed. You’ll have a small needle inserted into your arm to draw blood. The process usually takes a few minutes. If you’re pregnant, have a bleeding disorder, or are on blood-thinning medication, let your healthcare provider know before the test.

What to Expect After the Test

You may experience mild bruising, soreness, or swelling at the injection site. Apply ice if needed. Avoid strenuous activity for a few hours. If you experience heavy bleeding, excessive pain, or signs of infection (like fever), contact your doctor.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

High levels of RSV IgG antibodies suggest past infection or vaccination-induced immunity, which may reduce the risk of severe RSV illness. Low or absent levels could indicate no prior exposure or immunity, particularly relevant for high-risk groups. This test is not used to diagnose current RSV infection but helps assess long-term immunity.

Short name

RSV IgG Antibody

Frequently asked questions

How Does RSV IgG Antibody Testing Differ from RSV PCR Testing?
RSV IgG antibody testing looks for antibodies produced after infection or vaccination, indicating past exposure. In contrast, RSV PCR testing detects the virus itself in your respiratory samples (like nasal swabs) to diagnose an active infection. IgG testing is useful for immunity evaluation, while PCR is for diagnosing current illness.
Can RSV IgG Antibody Levels Change Over Time?
Yes, RSV IgG antibody levels can decline over months or years after infection or vaccination. While they may remain detectable, their concentration can decrease, potentially reducing long-term immunity. Regular monitoring may be needed for high-risk individuals.
Is This Test Covered by Insurance?
Whether this test is covered depends on your insurance plan and reason for testing. If recommended by your doctor for medical necessity (e.g., high-risk patient, vaccination evaluation), check with your insurer or provider for coverage details. Costs may vary by lab and location.
  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