When to test for COVID-19: rapid antigen tests and PCR
A single negative test does not always rule out infection. Timing, sample quality and the stage of illness affect test performance.
What tests can tell you
Testing can support decisions about reducing transmission and can help people at higher risk access clinical assessment early. Rapid antigen tests are convenient, while PCR and other molecular tests are generally more sensitive.
Interpreting results
A positive rapid test in someone with symptoms or a recent exposure is meaningful. A negative result can occur early or late in infection. If symptoms or exposure continue, follow local public-health guidance, which may include repeat testing.
After the result
If positive, reduce contact with others and seek clinical advice promptly if you are at higher risk. If negative but still ill, use respiratory precautions because another infection or an early COVID-19 infection is still possible.
Sources
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This content is general information, not a diagnosis or individual medical advice. Seek urgent help for severe or rapidly worsening symptoms.