Available tests




Countries around the world developed tests independently and in partnership with others.

Nucleic acid tests

Tests developed in China, France, Germany, Hong Kong, Japan, the United Kingdom, and the US targeted different parts of the viral genome. WHO adopted the German system for manufacturing kits sent to low-income countries without the resources to develop their own.

PowerChek Coronavirus looks for the "E" gene shared by all beta coronaviruses, and the RdRp gene specific to SARS-CoV-2.

Abbott Laboratories' ID Now nucleic acid test uses isothermal amplification technology. The assay amplifies a unique region of the virus's RdRp gene; the resulting copies are then detected with "fluorescently-labeled molecular beacons". The test kit uses the company's "toaster-size" ID Now device, which is widely deployed in the US. The device can be used in laboratories or in point of care settings, and provides results in 13 minutes or less.

Primerdesign offers its Genesig Real-Time PCR Coronavirus (COVID‑19). Cobas SARS-CoV-2 Qualitative assay runs on the Cobas® 6800/8800 Systems by Roche Molecular Systems. They are offered by the United Nations and other procurement agencies.

Antigen tests

Quidel's "Sofia 2 SARS Antigen FIA" is a lateral flow test that uses monoclonal antibodies to detect the virus's nucleocapsid (N) protein. The result is read out by the company's Sofia 2 device using immunofluorescence. The test is simpler and cheaper but less accurate than nucleic acid tests. It can be deployed in laboratories or at point of care and gives results in 15 minutes. A false negative result occurs if the sample's antigen level is positive but below the test's detection limit, requiring confirmation with a nucleic acid test.

Serology (antibody) tests

Antibodies are usually detectable 14 days after the onset of the infection. Multiple jurisdictions survey their populations using these tests. The test requires a blood draw.citation needed

Private US labs including Quest Diagnostics and LabCorp offer antibody testing upon request.

Antibody tests are available in various European countries. Quotient Limited developed a CE marked COVID-19 antibody test.

Roche offers a selective ELISA serology test.

A summary review in BMJ has noted that while some "serological tests … might be cheaper and easier to implement at the point of care than RT-PCR", and such testing can identify previously infected individuals, "caution is warranted … using serological tests for … epidemiological surveillance". The review called for higher quality studies assessing accuracy with reference to a standard of "RT-PCR performed on at least two consecutive specimens, and, when feasible, including viral cultures." CEBM researchers have called for in-hospital 'case definition' to record "CT lung findings and associated blood tests" and for the WHO to produce a "protocol to standardise the use and interpretation of PCR" with continuous re-calibration.

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