By Daniel R. Lucey MD, MPH, FIDSA
Retrospective testing for SARS-CoV-2 virus and antibody could be (or has been) done using blood and other samples highly likely to have been obtained from the 18 mammalian species (including masked palm civet, racoon dogs, and mink) reported in the Wuhan wet markets, May 2017-November 2019, as part of a study on “Severe Fever with Thrombocytopenia (SFTS)” published not until June 7, 2021.
Photos from the Wuhan Huanan seafood market include racoon dogs, hedgehogs, bamboo rats, and badgers with the description of “Poor welfare of animals on sale in Huanan seafood market.”
A tick found on a hedgehog is emphasized in the legend to Figure 2, given that ticks are thought to be the main transmission route from animals to humans of the bunyavirus first discovered in a 2009 outbreak in Hubei and Henan provinces of Severe Fever with Thrombocytopenia Syndrome. (An aerosol route is less commonly implicated in nosocomial, familial, and other cases of persons-to-person transmission of this bunyavirus causing SFTS).
Although not explicitly stated in this June 7 paper in Nature, it is highly likely that samples of blood and perhaps respiratory and other types of samples from the animals surveyed on a monthly basis in Wuhan wet markets from May 2017-November 2019 would have been obtained.
In addition, blood samples from humans working in these wet markets, including the Wuhan Huanan seafood market, would very likely have been obtained to test for bunyavirus and antibody to the bunyavirus that causes SFTS. (Less likely, even respiratory samples from humans may have been obtained).
Such samples from both animals and humans in the Wuhan wet markets could be tested for antibody to SARS-CoV-2, as well as any respiratory samples for SARS-CoV-2 itself, month-by-month over 30 months from May 2017-November 2019.
If antibody-negative results were demonstrated in 2017 and 2018, followed by some antibody (and perhaps virus)-positive results in 2019, then a “look back” retrospective study of the supply chain of animals and the epidemiology of the humans could provide clues to the COVID origins in terms of emergence timeline, geography, animal species, and human infections.
Daniel Lucey, M.D. MPH, FIDSA, FACP, is a Clinical Professor of Medicine at Dartmouth Geisel School of Medicine, Infectious Disease adjunct Professor at Georgetown Medical Center, senior scholar at Georgetown Law, Anthropology Research Associate at the Smithsonian Museum of Natural History and a member of the Infectious Diseases Society of America Global Health Committee. He served as a volunteer to outbreaks overseas including hands-on Ebola patient care in Sierra Leone and Liberia (Doctors without Borders) 2014, MERS 2013, SARS 2003, as well as HIV, H5N1, Zika, yellow Fever, and pneumonic plague 2017 (with WHO/USAID/CDC). Since Jan. 6, 2020 he has contributed more than 100 posts to Science Speaks on COVID-19 and traveled to China in February 2020. He initially proposed, then fundraised and helped design the content for 2018-2022 Smithsonian Exhibition on Epidemics due to zoonotic viruses. From 1982-1988 he trained at University of California San Francisco and Harvard and was an attending physician at the NIH (NIAID) in the 1990s while in the U.S. Public Health Service.