For instance, he took a close looked at swab Q61: the swab featured in the New York Times article that contained a great deal of raccoon dog genetic material and was also purportedly positive for SARS-CoV-2. What Bloom found was that the swab indeed contained a significant quantity of raccoon dog genetic material but very low amounts of SARS-CoV-2 genetic material.
As Bloom reports in his paper, “This sample tested negative by RT-qPCR and appears to have been called positive on the basis of containing 1 of ~200,000,000 reads that mapped to SARS-CoV-2.”
In other words, as Sergei Pond explained, the swab Q61 that got all that media attention was not all it was reported to be.
“One read out of 200,000,000 is completely statistically insignificant,” said Pond. “It really had no SARS-CoV-2. There is no evidence based on genetic analysis there was SARS-CoV-2 in that sample. One read out of 200,000,000 — it could have been a low level of trace contamination.”
What’s more, as Bloom’s preprint reports, Q61 was the only swab above a
certain threshold for raccoon dog genetic material that contained any SARS-CoV-2 RNA at all: “13 of the 14 samples with at least 20% of their chordate mitochondrial material from raccoon dogs contain no SARS-CoV-2 reads, and the other sample [swab Q61] contains just 1 of ~200,000,000 million reads mapping to SARS-CoV-2.” When Bloom plotted the quantity of animal genetic material found in the swabs with their SARS-CoV-2 RNA content, he determined that there was in fact a negative correlation between the abundance of SARS-CoV-2 and genetic material from raccoon dogs in the swabs.
“I wouldn’t read too much into these correlations, but to the extent SARS-CoV-2 genetic material is associated with any of the material from these species, it is not with species that we think could have been infected with SARS-CoV-2,” he said. “It just sort of suggests that by the time these samples were collected, SARS-CoV-2 was all over the place, probably unrelated to the distribution of the animals and animal products [at the market].”