Section of the Jan–Feb 2021 WHO-China joint mission’s report covering environmental and animal sampling at the Huanan market: describes the market’s closure and initial disinfection (1 Jan 2020), an early round of environmental sampling (585 samples collected by end of Jan 2020, ~33 positive, mostly from the market’s west/wildlife side — a subset of what the later China CDC papers report in full), and negative animal-product testing available at that time. Also documents the market’s cold-chain supply lines from 20 countries as a competing “imported frozen/wildlife product” hypothesis for introduction. Superseded in coverage (though not in institutional weight) by S-16 - Liu, Gao et al. — Surveillance of SARS-CoV-2 at the Huanan Seafood Market (Nature), which reports the fuller Jan–Mar 2020 campaign. relevance_note: earliest official record of market environmental sampling and the first public numbers (585 samples/33 positive) that the later, larger China CDC dataset supersedes.