What this test measures
This is a general SARS-CoV-2 antibody test, typically delivered as a rapid card test detecting IgM and IgG against the virus. Some lab panels under this name combine antibody testing with antigen or RNA detection depending on the catalogue.
For accurate clinical use, current SARS-CoV-2 testing is split into: (1) RT-PCR for active infection diagnosis, (2) rapid antigen tests for quick infection diagnosis, and (3) antibody tests (IgG, IgM, total, neutralising) for past exposure or vaccine response. Verify with the lab which version is offered.
Why it matters
In current Indian practice, RT-PCR or rapid antigen tests are used to diagnose active COVID-19, while antibody tests confirm past exposure or vaccine response. A generic "COVID-19 test" entry in a catalogue could refer to any of these.
For a patient with symptoms, RT-PCR is the standard. For someone curious about past exposure, antibody tests are appropriate. For most healthy adults, routine COVID antibody testing is not recommended for clinical decisions per WHO, CDC, and ICMR.
How to prepare
No fasting required. Confirm with the collection team which exact test is being done (PCR, antigen, or antibody) so the right sample type is collected.
Markers & reference ranges
Reference ranges below are typical adult values. Your lab's reported range may differ slightly based on the assay platform and patient demographics — always read your report against the range printed on it.
| Marker | Normal range | If low | If high |
|---|---|---|---|
| SARS-CoV-2 Antibody (Reactive / Non-reactive)[1][2] | Depends on context — vaccinated/recovered usually reactive | Non-reactive — no detectable antibody. Either never exposed/vaccinated, very early after exposure, or rare non-responder. | Reactive — antibody present from past infection, vaccination, or both. Does not indicate current infection. |
COVID-19 testing — which test for which purpose
| Need | Test | Sample |
|---|---|---|
| Active infection diagnosis | RT-PCR | Nasopharyngeal swab |
| Quick infection screen | Rapid Antigen Test | Nasal swab |
| Past infection confirmation | IgG or Total Antibody | Serum |
| Vaccine response check | IgG Quantitative (BAU/mL) | Serum |
| Functional immunity | Neutralising Antibody | Serum |
Frequently asked questions
What exactly is being tested when I book "COVID-19"?
Typically a rapid antibody test for IgM/IgG. Confirm with the lab — for active infection diagnosis, choose RT-PCR or rapid antigen instead.
Should I test antibody if I have current symptoms?
No — antibody develops 1–4 weeks after infection. For current symptoms, RT-PCR or rapid antigen is appropriate.
Is routine COVID antibody testing recommended?
No. WHO, CDC, and ICMR do not recommend routine antibody testing for clinical decisions in healthy adults.
When should I test antibody?
In immunocompromised patients to assess vaccine response, for research and serosurveys, and to support past-COVID diagnosis if RT-PCR was never done.
Will a positive antibody mean I cannot get COVID-19 again?
No — re-infection occurs, especially with variant emergence. Antibody is one factor among many that contribute to protection.
How long after vaccination should I test antibody?
At least 2–4 weeks after the last dose for a stable response.
Is the rapid antibody test reliable?
Modern rapid tests have ~85–95% sensitivity and ~92–98% specificity. CLIA or ELISA confirmation is preferred for clinical decisions.
Related Infectious Disease tests
Tests commonly ordered alongside COVID-19, or that help interpret an unexpected result.
Sources & references
- ICMR India — COVID-19 Guidance · accessed 2026-05-30T00:00:00.000Z
- WHO — COVID-19 Antibody Testing Guidance · accessed 2026-05-30T00:00:00.000Z
- CDC — COVID-19 Testing · accessed 2026-05-30T00:00:00.000Z
- NIV Pune — COVID-19 Testing · accessed 2026-05-30T00:00:00.000Z
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