Research will offer the best exit strategy, and we will do everything we can to help researchers and clinicians realize that goal. What’s in a test

Most testing for COVID-19 is currently done on viral genetic material from nose and throat swabs, using a workhorse tool of molecular biology known as reverse transcription polymerase chain reaction (RT-PCR). The test works by amplifying a specific genetic sequence in the virus. Short complementary sequences known as primers help to get the copying started. But PCR can only detect virus while it is present in a person. It doesn’t reveal much about a resolved infection. It’s also known to sometimes produce false positives if reagents in a lab become contaminated. Labs worldwide have customized their PCR tests for SARS-CoV-2, using different primers targeting different sections of the virus’s genetic sequence. Who got to it quickly? Several countries have been able to test a huge number of people (see Unequal testing). South Korea responded speedily and effectively after the first cases emerged there in late January, deploying a combination of rapid testing and monitoring people who were in contact with those who had tested positive. Regulations enacted after a 2015 outbreak of Middle East respiratory syndrome allowed for rapid approval of a version of the WHO’s test, and four companies were scaling it up to test a total of 10,000 people a day, according to reporting by the independent newsroom ProPublica. Source : https://www.nature.com/articles/d41586-020-00827-6