Chinese researchers isolated and mapped the virus that causes Covid-19 in late December 2019, at least two weeks before Beijing revealed details of the deadly virus to the world, congressional investigators said, raising questions anew about what China knew in the pandemic’s crucial early days. Documents obtained from the U.S. Department of Health and Human Services by a House committee and reviewed by The Wall Street Journal show that a Chinese researcher in Beijing uploaded a nearly complete sequence of the virus’s structure to a U.S. government-run database on Dec. 28, 2019. Chinese officials at that time were still publicly describing the disease outbreak in Wuhan, China, as a viral pneumonia “of unknown cause” and had yet to close the Huanan Seafood Wholesale Market, site of one of the initial Covid-19 outbreaks. China only shared the virus’s sequence with the World Health Organization on Jan. 11, 2020, according to U.S. government timelines of the pandemic.

The extra two weeks could have proved crucial in helping the international medical community pinpoint how Covid-19 spread, develop medical defenses and get started on an eventual vaccine, specialists have said.

The documents describing a new timeline were obtained by Republicans on the House Energy and Commerce Committee after the committee threatened to subpoena HHS. Melanie Egorin, HHS assistant secretary for legislation, wrote last month to the committee’s chair, Rep. Cathy McMorris Rodgers (R., Wash.), that Ren submitted the virus sequence on Dec. 28, 2019, to a genetic database, GenBank, run by the U.S. National Institutes of Health.

The sequence that Ren provided in December 2019 was never published and was deleted from the database on Jan. 16, 2020, after NIH, following its protocols, asked her for more technical details and she didn’t respond, Egorin wrote. It is unclear why Ren didn’t respond. On Jan. 12, NIH received and published a SARS-CoV-2 sequence from another source. “The sequence published on Jan. 12, 2020, was nearly identical to the sequence that was submitted by Lili Ren,” Egorin told the committee.

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