On Dec. 6, 2024, Shi Zhengli, the Chinese virologist at centre of COVID lab-leak theory, has presented evidence that her lab has not worked with close relatives of SARS-CoV-2. Shi was leading coronavirus research at the Wuhan Institute of Virology (WIV), a high-level biosafety laboratory, when the first cases of COVID-19 were reported in that city in 2019.

The latest analysis, which has not been peer reviewed to date, includes data from the whole genomes of 56 new betacoronaviruses, the broad group to which SARS-CoV-2 belongs, as well as some partial sequences. All the viruses were collected between 2004 and 2021. The study showed that none of the viruses stored in her freezers are the most recent ancestors of the virus SARS-CoV-2.

Earlier in the year, Shi moved from the WIV to the Guangzhou Laboratory, a newly established national research institute for infectious diseases.