Wikipedia:WikiProject COVID-19/Translation Task Force/COVID-19 testing (long)

Laboratory testing for the respiratory coronavirus disease 2019 (COVID-19) and the associated SARS-CoV-2 virus includes methods that detect the presence of virus and those that detect antibodies produced in response to infection. Detection of antibodies, called serology, can be used both for clinical purposes and population surveillance. As of March 2020, most countries have limited virus testing to vulnerable individuals, so it is not possible to reliably calculate the prevalence of the virus. Detection of the virus is frequently done by real time reverse transcription polymerase chain reaction (rRT-PCR) method on respiratory samples obtained by various methods, including nasopharyngeal swab or sputum sample. Blood test for large scale testing of individuals to detect antibodies produced by the body as a result of an infection is under development. Chest CT scans can sometimes help identify and characterize lung pathology, and have yielded non-specific findings with COVID-19 infection. Some countries have drive-through testing where samples are taken from suspected individuals by a healthcare professional using appropriate precautions.

Virus detection
COVID-19 virus can be detected using real time reverse transcription polymerase chain reaction (rRT-PCR). The test can be done on respiratory samples obtained by various methods, including nasopharyngeal swab or sputum sample. Results are generally available within a few hours to 2 days.

Antibody detection
Part of the immune response to infection is the production of antibodies including IgM and IgG. These can be used to detect infection in individuals, to determine immunity, and in population surveillance. Blood samples are usually tested for antibody detection. As of March 2020, these tests have not yet been made available for large scale testing.

CT scans
Most common CT scan findings were bilateral ground-glass attenuation (patchy or diffuse) with subpleural dominance, crazy paving and consolidations at later stages. These findings are nonspecific and found as well in other types of pneumonia. Thus, CT scan is not recommended for initial screening of COVID-19 as of March 2020.