A World Health Organization investigation into the origins of the coronavirus in China found that there may have been cases of coronavirus in China two months earlier than originally identified.
The four-week investigation showed that in central China there were more than 90 people who were hospitalized for coronavirus symptoms two months before December 8, 2019, the day China says the first coronavirus patient was found, Wall Street Journal reported.
The WHO wants China to test blood samples from a larger population in the fall of 2019 to confirm its theory, but Chinese authorities say they are not yet allowed to test them, WHO investigators told the WSJ.
Chinese officials performed antibody tests on some of the 90 patients who were diagnosed with coronavirus symptoms last fall, but no antibodies were found in them. However, WHO investigators believe they have just waited too long to test them and the antibodies have subsided, says WSJ.
It is unclear how long the antibodies to the body survive for coronavirus, as there are debates as to whether they last for weeks or months.
Blood samples and medical records were checked, but there was no evidence that the virus appeared before December 2019, Liang Wannian, head of the coronavirus group for China’s National Health Commission, said on Tuesday,
More studies and blood tests will be needed to determine if the coronavirus existed before December 2019.