Supports· strongCOV-E005
Susceptible-wildlife DNA in the positive samples — and the authors' own limitation
- what the source states
- From the published abstract: investigators "find increased SARS-CoV-2 positivity near and within a wildlife stall. We identify wildlife DNA in all SARS-CoV-2-positive samples from this stall, including species such as civets, bamboo rats, and raccoon dogs, previously identified as possible intermediate hosts." From the Results: "The five SARS-CoV-2-positive samples from wildlife stall A contained mtDNA from raccoon dogs, hoary bamboo rats, dogs … and European rabbits. Amur hedgehog and Malayan porcupine mtDNA was present in four samples … and one sample contained masked palm civet mtDNA." The authors then state the limitation directly: "Although either animal or human viral shedding is consistent with these data, only a zoonotic origin of SARS-CoV-2 directly predicts co-detection of SARS-CoV-2 and wildlife genetic material." And: "It is not possible to conclude which of these species may have been infected and/or introduced the virus to the market from these data alone."
- what we infer
- The strongest affirmative market evidence, and its limits are stated by the people who produced it rather than by critics. The asymmetry the authors identify is genuine and easy to miss: co-detection is what zoonosis specifically predicts, even though human shedding after a zoonotic event would produce the same pattern. Detection is uneven across species, which the flat species lists in circulation obscure.
- limitations
- A reanalysis of the same Chinese CDC environmental data underlying the surveillance paper, sharing authors with the market epicenter paper: one evidence stream, not an independent confirmation.
- The authors note that a correlational analysis of this data cannot reliably show whether any particular species was infected.