MIT biologist Kevin Esvelt has alleged that Russian authorities have sequenced an infectious agent associated with a laboratory worker's death but have not disclosed its identity. He made the claim in an X thread on 5 October, without presenting laboratory data establishing that sequencing had occurred or that officials were withholding a result.
Darya Shipilova, 28, died on 2 October after developing severe pneumonia. Russian authorities have described its cause as undetermined and said testing had not identified microorganisms associated with her work. On 7 October, the country's public-health regulator said precautionary measures were being wound down.