In March 2023 new metagenomics data and SARS-CoV-2 sequences appeared on GISAID (the Global Initiative for Sharing Avian Influenza Data) and were available to researchers across the world for a short period of time. Although access was restricted to allow further updates, WHO was notified of this data and later learnt that they are the basis for an update to a paper that is being re-submitted to Nature by China CDC.
A statement from WHO in March indicated that discussions between WHO, SAGO, and China CDC, with participation from “some of those who had accessed the data”, enabled the organisations to “gauge the significance of this data and the analyses of this data”.
New data, new ideas
WHO suggests that the presentations from China CDC and “invited international researchers” identified newly available data from the Huanan Seafood Wholesale Market. This included metagenomic data of environmental samples from stalls and wastewater collection sites from as early as January 2020.
Not only were SARS-CoV-2 sequences available, but “mitochondrial DNA of several animal species” and human DNA. Among the animal species, DNA from “wild raccoon dogs, Malaysian porcupine, and bamboo rats” were included in “SARS-CoV-2 positive environmental samples”. WHO believes that these findings demonstrate the presence of animals at the market “shortly before the market had been cleared” on the 1st of January 2020 during public health measures.
“These results provide potential leads to identifying intermediate hosts of SARS-CoV-2 and potential sources of human infections in the market.”
WHO refers to a pre-print by Liu et al, 2022, which indicates that raccoon dogs were not among the animals tested in early 2020. However, the presence of “high levels of raccoon dog mitochondrial DNA” in this data does indicate that raccoon dogs and other animals may have been present at the market before it was cleaned.
SAGO encourages sharing
SAGO states that it will continue to evaluate “any and all” scientific data that are shared by researchers from “anywhere in the world”.
“SAGO encourages any and all data related to the studying of the origins of SARS-CoV-2 be made available immediately for robust and comprehensive review.”
Although previously accused of neglecting the investigations into the origins of the COVID-19 pandemic, SAGO continues to “strongly” recommend that researchers in China investigate the “upstream sources of the animals and animal products present” at the Huanan market before its closure in January 2020. As Dr Mike Ryan emphasised in a WHO briefing in February 2023, WHO relies on Member States’ independent research to be shared with the global scientific community.
For more on SARS-CoV-2 data and vaccine development, join us at the World Vaccine Congress in Washington next month.