RT - PCR

Reverse transcription PCR, or RT-PCR, allows the use of RNA as a template. An additional step allows the detection and amplification of RNA. The RNA is reverse transcribed into complementary DNA (cDNA), using reverse transcriptase.

This test uses a sample of mucus typically taken from a person’s nose or throat. The test may also work on saliva — that’s under investigation. It looks for the genetic material of the coronavirus. The test uses a technology called PCR (polymerase chain reaction), which greatly amplifies the viral genetic material if it is present. That material is detectable when a person is actively infected.

This test identifies people who are currently infected with the coronavirus. It may be used as a quick test to detect active infections. Initially it will not be used to diagnose disease, but it may be used to screen people to identify those who need a more definitive test.

Antigen tests can identify virus in nose and throat secretions.

Antibody tests identify people who have previously been infected with the coronavirus. They do not show whether a person is currently infected. This is primarily a good way to track the spread of the coronavirus through a population.

This is a blood test. It looks for antibodies to the coronavirus. Your body produces antibodies in response to an infectious agent such as a virus. These antibodies generally arise after four days to more than a week after infection, so they are not used to diagnose current disease.

• Researchers do not expect antigen test to be as accurate as the PCR diagnostic test, but it is possible the antigen tests could be used to screen patients for infection.
• There are more than 120 antibody tests on the market.A few tests have voluntarily submitted to extra FDA approval. Other tests are being validated by individual medical labs or university researchers.
• Rt – PCR test are the most reliable tests. However, a few days may pass before the virus starts replicating in the throat and nose, so the test won’t identify someone who has recently been infected.