An investigation by the World Health Organization in China into the origins of the coronavirus found that there may have been cases of coronavirus in China two months earlier than originally identified.
The four-week investigation showed that there were more than 90 people in central China who were hospitalized for coronavirus symptoms two months before December 8, 2019, the day China says the first coronavirus patient was found, the Wall Street Journal reported.
WHO wants China to test blood samples from a broader population since autumn 2019 to confirm its theory, but Chinese officials said they are not yet allowed to test them, WHO researchers told WSJ.
Chinese authorities tested antibodies on some of the 90 patients who had symptoms of coronavirus last fall, but no antibodies were found in them. However, WHO researchers think they have waited a long time to test them and the antibodies have decreased, says WSJ.
It is unclear how long the antibodies survive in the body for the coronavirus, as there is a debate as to whether they last a few weeks or a few months.
Blood samples and medical records were checked, but there is no evidence that the virus appeared before December 2019, Liang Wannian, head of the coronavirus panel at the National Health Commission of China, said on Tuesday,
Further studies and blood samples will be needed to determine whether the coronavirus existed before December 2019.