Could There be Transmission of SARS-CoV-2 in Cats and Pigs to Humans?

Kansas State University researchers have discovered 2 important findings published in recent studies that relate to the COVID-19 pandemic. The studies found that cats can be asymptomatic carriers of the SARS-CoV-2 virus, while pigs are most likely not significant carriers.

The studies, published in Emerging Microbes & Infections, took place at Kansas States Biosecurity Research Institute. The focus was on domestic cats’ susceptibility to disease, infection and transmission. The researchers found that, while cats might not show any signs of the virus, they are still able to shed it through oral, rectal and nasal cavities. They are also able to spread it to other cats, but research still needs to be done as to whether they can transmit it to humans.

There are around 95 million house cats in the United States alone, with somewhere between 60 to 100 million feral cats in the country. "Our findings are important because of the close association between humans and companion animals,” Jürgen A. Richt, PhD, the Regents distinguished professor at Kansas State University’s College of Veterinary Medicine said. "This efficient transmission between domestic cats indicates a significant animal and public health need to investigate a potential human-cat-human transmission chain."

The study also concluded that pigs don’t look to be susceptible to SARS-CoV-2, and do not seem to be able to spread the virus to other contact animals.

"Pigs play an important role in U.S. agriculture, which made it important to determine the potential SARS-CoV-2 susceptibility in pigs," Richt said. "Our results show that pigs are unlikely to be significant carriers of SARS-CoV-2."

Future studies have been discussed to continue the research into the transmission of SARS-CoV-2 in cats and pigs. Another point of interest for the team, where more research is planned, is whether or not cats are able to be reinfected with the virus once they have recovered from it.

"This research is important for risk assessment, implementing mitigation strategies, addressing animal welfare issues, and to develop preclinical animal models for evaluating drug and vaccine candidates for COVID-19," Richt said. These types of studies, which help researchers understand the mechanisms of infection, play a critical role in furthering the knowledge of current and future pandemics.