Asymptomatic carriers of coronavirus COVID-19 may not be dangerous for others, a group of scientists believe. This refers to people who test positive but have no signs of disease – studies have shown that the virus from their swabs was not viable and people in contact with asymptomatic carriers did not become ill.

In May 2020, Wuhan, China, conducted comprehensive testing of residents for COVID-19: nearly 10 million people over the age of six, about 93% of the city’s population. Most had not previously had a confirmed diagnosis of coronavirus infection.

An international team of scientists from China, Great Britain and Australia analyzed the results. Only 300 people tested positive for COVID-19, none of whom had symptoms of the disease.

These people were quarantined and monitored for two weeks until they tested negative. No signs of the disease appeared in those infected during that time.

The researchers also analyzed the close contacts of 300 COVID-19 carriers with other people. There were 1,174 in total, and none tested positive.
“The asymptomatic positive cases found in this study are unlikely to be contagious,” the researchers concluded.

The researchers caveat is that signs of COVID-19 may be latent but still present. In this case, people cannot be considered asymptomatic carriers, much less non-infectious.