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15 kwi 2021 · SARS-CoV-2 is the novel coronavirus that causes COVID-19. The spectrum of asymptomatic, presymptomatic, and symptomatic SARS-CoV-2 transmission presents challenges for evaluating...
What do COVID-19 PCR test results mean? A positive test result means that it's likely that you have an infection with SARS-CoV-2. This could be due to asymptomatic infection, but if you have symptoms, then this infection is called COVID-19.
This guide describes the various diagnostic tests that are available to detect the presence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection resulting in coronavirus disease (COVID-19), or an immune response to this infection, to help clinicians make more informed decisions based on the results of these tests.
Both platforms search for 2 targets; target 1 that is specific to SARS-CoV-2 (the coronavirus causing COVID-19) and target 2 for general Corona Viruses (including but not limited to SARS-CoV-2). Positive results: You have tested positive for Sars-CoV-2, the virus causing COVID-19.
SARS-CoV-2 reverse transcriptase–polymerase chain reaction (RT-PCR) testing is highly sensitive (99%) but less specific (approximately 95%) for contagious COVID-19 and may be positive for ≥90 days after infection. Viral antigen tests have lower analytic sensitivity than RT-PCR but are more specific for contagious disease
Interpreting the result of a test for covid-19 depends on two things: the accuracy of the test, and the pre-test probability or estimated risk of disease before testing. A positive RT-PCR test for covid-19 test has more weight than a negative test because of the test’s high specificity but moderate sensitivity.
This Viewpoint describes how to interpret 2 types of diagnostic tests commonly in use for SARS-CoV-2 infections—reverse transcriptase–polymerase chain reaction (RT-PCR) and IgM and IgG enzyme-linked immunosorbent assay (ELISA)—and how the results may vary over time (Figure). Figure.