Rats in New York City, USA were exposed to multiple variants of Sars-CoV-2 (Alpha, Delta, Omicron). This is according to a study published in the journal mBio from the American Society for Microbiology (Source 1).

Rats are widely present in major American cities, the researchers point out in a press release (Source 2). “ For example, New York City alone has about eight million wild rats. These wild rats have many opportunities to interact with humans. Two previous studies have suggested that rats in Asia (Hong Kong) and Europe (Belgium) were exposed to SARS-CoV-2; however, it is unclear which variant of SARS-CoV-2 these rats were exposed to in the two studies “say the scientists.

In the fall of 2021, a team from the Animal and Plant Health Inspection Service of the United States Department of Agriculture took samples and analyzes from Norway rats (Rattus norvegicus) At New York. To do this, rat traps have been installed in the city’s parks, and around the manholes. In the end, 79 rats were thus caught for virological studies and sequencing of their genome. In all, 13 of the 79 rats tested positive for Covid-19, or at least carrying a version of the virus. The study further showed that the Alpha, Delta and Omicron variants may well cause infection in rats.

If these results may seem trivial, since it has been shown that our pets could also contract the virus, they raise questions about the possibility of new variants and a return of these to the human species.

“ Our results highlight the need for further surveillance of Sars-CoV-2 in rat populations to possible secondary zoonotic transmission to humans “said the lead author of the study, Professor Henry Wan, director of the Center for Influenza and Emerging Infectious Diseases at the University of Missouri. The goal is to “ determine if the virus is circulating in animals and evolves into new strains who could pose a risk to humans “.