A number of reported cases of coronavirus patients relapsing after overcoming the disease were actually due to testing failures, South Korean scientists say.
Researchers at the South Korean centre for disease control and prevention (CDC) now say it is impossible for the COVID-19 virus to reactivate in human bodies.
There have been more than 10,000 confirmed coronavirus cases in South Korea, with 245 deaths - a 2.3% fatality rate, which is lower than the 3.4% average as stated by the World Health Organisation.
A total of 277 patients in the country were believed to have fallen ill for a second time, as had patients in China and Japan.
This prompted concerns that the virus could be mutating so quickly that people were not necessarily immune to catching it again.
However, genetic analyses of the virus have not found any substantial changes which would effectively disguise it from the immune system.