A medical worker takes a swab sample from a citizen for nucleic acid testing at Heping District in Tianjin, north China, July 24, 2022. (PHOTO / XINHUA)

BEIJING – China provided all relevant tracing data that it possessed at the time throughout the first phase of the joint research for COVID-19 origins, without withholding any information, according to Shen Hongbing, director of the Chinese Center for Disease Control and Prevention.

Recently, certain officials and experts of the World Health Organization have made arbitrary remarks and rashly denied the results at that time, which completely goes against the scientific spirit.

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This is a rude and disrespectful offense to the scientists from various countries who participated in the early-stage tracing work and is a manifestation of politicizing the tracing of COVID-19, which is unacceptable to the Chinese scientific community and cannot be accepted by the global scientific community, Shen added.

'Humans may have passed it to animals'

Humans infected by the COVID-19 virus may have introduced the novel coronavirus to susceptible animals at the Huanan seafood market in Wuhan, Hubei province, where the first COVID-19 cases were reported in China, Chinese researchers said on Saturday. 

These findings suggest that the virus was introduced to the market by human carriers.

Tong Yigang, Beijing University of Chemical Technology

On Wednesday, the journal Nature published a genome analysis of swabs collected at the market from January to March 2020. 

The dataset contained over 1,300 samples collected from the environment and animals present.

Tong Yigang, dean of the College of Life Science and Technology at Beijing University of Chemical Technology, said in a press briefing that no animal swab samples collected had tested positive for the novel coronavirus, but 73 swabs from the environment had returned positive. 

After further analysis, researchers discovered that the viral genetic sequence from the environmental sample was almost identical to those collected from early patients. 

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"These findings suggest that the virus was introduced to the market by human carriers," Tong said, adding that there is no definitive proof that the COVID-19 virus had originated from an animal-to-human spillover event.