New medical reports from China have shown that people who have no symptoms and initially test negative for COVID-19 can still spread the virus.
It showed how a 20-year-old woman from Wuhan infected five relatives in the Chinese city of Anyang.
Published by the Journal of the American Medical Association, the study offered new evidence that the virus can spread asymptomatically.
It showed that "none of the patients had visited Wuhan or been in contact with any other people who had travelled to Wuhan" - except their 20-year-old relative.
So far, China has reported 76,288 cases, including 2,345 deaths.
Meanwhile, the WHO confirmed that more than 1,200 cases of the virus have been confirmed in 26 countries, with eight deaths.
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