Deer & SARS CoV2 –By Prof. Fleury
Prof. H. Fleury – University of Bordeaux and CNRS UMR 5234
SARS-CoV 2 has been detected in domestic animals (cats, dogs) as well as in captive animals (tigers, lions, deer, mink) and rodents. The list of experimentally infected animals further expands the zoo-tic epidemic potential of infection.
Coming from the bat under conditions that are still discussed. Whether it was from direct transmission or via an intermediate host such as the camel for MERS CoV; even the civet for SARS CoV, or a laboratory accident?
SARS-CoV2, which has caused a pandemic in humans, can now be transmitted by Homo-Sapiens to animals that will serve as a reservoir and eventually return the virus to humans after modifying it by mutation. This was the case of mink in the Netherlands leading to the government decision to euthanize these animals.
In the United States, reports on the massive infection of deer since 2020 have been made. In a PNAS article (Reports of the US Academy of Sciences) 2021, Chandler College analyzed the sera of 624 deer in pre-pandemic and pandemic periods in 4 states, including New York, Illinois, Michigan, and Pennsylvania; neutralizing antibodies against SARS CoV2, witnesses of infection, appear in 2020 to reach 40% of animals in 2021. Another study from Hale Col. BioRxiv 2021 confirms that deer are actively infected with viral production associated with positive PCR without showing clinical signs; thus 36% of the deer studied in Ohio are carriers of the virus.
Sequencing of SARS CoV2 strains shows that these strains contain the variants seen in humans in the USA. Deer would be contaminated directly from humans on farms, or indirectly by water, contaminated by human stool. The deer thus becomes a reservoir for humans and it is feared that mutants will be generated in this species before being transmitted to humans.
The question of infection of cattle also arises to the extent that it has been demonstrated in the laboratory that the respiratory cells of cattle allow viral replication, which is not the case of pig cells. (Field studies will be required). As we can see, the SARS CoV2 pandemic holds surprises, in particular by highlighting the role of Humans in the contamination of wild and domestic animals. Pending European and French data seem appropriate to advise hunters to be cautious, and take necessary precautions when handling deer.
