The ideal HIV test would correctly identify all people who are HIV positive and HIV negative 100% of the time. Although many HIV tests are extremely accurate, they do not reach 100% accuracy.
A false negative is a test result that says that a person does not have HIV when in fact they do.
False negatives most often occur when people test in the first few weeks after infection, during the "window period" of a test. At present, the markers of infection (p24 antigen and antibodies) sought by the tests may be absent or rare. The tests cannot reliably detect all cases of infection during the window period.
The chances of having a false negative result therefore depend on the rate of new HIV infections (incidence) in a community. In a low incidence environment with very little continuous HIV transmission, most of the HIV infections that need to be tested will be infections that people have had for months or years. For these long-standing infections, the tests are extremely accurate and therefore false negatives are extremely rare.
However, in a community where the incidence of HIV is higher and HIV transmission continues, a higher proportion of HIV infections whose tests need to be detected will be recent infections (which people have had for only a few weeks). For these, the tests are less reliable and false negatives can occur.
False negatives have also been reported in people taking antiretroviral drugs, whether for HIV treatment, pre-exposure prophylaxis (PrEP) or post-exposure prophylaxis (PEEP).
Research Article: Journal of AIDS & Clinical Research
Research Article: Journal of AIDS & Clinical Research
Research Article: Journal of AIDS & Clinical Research
Research Article: Journal of AIDS & Clinical Research
Research Article: Journal of AIDS & Clinical Research
Research Article: Journal of AIDS & Clinical Research
Editor Note: Journal of AIDS & Clinical Research
Editor Note: Journal of AIDS & Clinical Research
Research Article: Journal of AIDS & Clinical Research
Research Article: Journal of AIDS & Clinical Research
Posters & Accepted Abstracts: Journal of Clinical Case Reports
Posters & Accepted Abstracts: Journal of Clinical Case Reports
Scientific Tracks Abstracts: Journal of Clinical Case Reports
Scientific Tracks Abstracts: Journal of Clinical Case Reports
Scientific Tracks Abstracts: Journal of AIDS & Clinical Research
Scientific Tracks Abstracts: Journal of AIDS & Clinical Research
Journal of AIDS & Clinical Research received 5264 citations as per Google Scholar report
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