A new study has found that ferrets and cats are susceptible to contracting SARS-CoV-2 but not dogs, ducks, chickens and pigs. The yet to be peer-reviewed study published in bioRxiv suggests that these findings can be important for vaccine and antiviral drug development.
But there is no cause for panic among pet keepers or cat lovers yet because these are only lab experiments and there has been no study on whether cats can pass on the infection to humans. Also, its not clear from the study which species of cats have been used for the experiments.
According to the authors from Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences and National High Containment Laboratory for Animal Diseases Control and Prevention in China, the objective of the experiments were to understand how the virus behaves in animals and which animals can be used to model the efficacy of control measures in humans (such as drugs or vaccines). The scientists isolated the virus from an environmental sample in the Hunan Seafood Market in Wuhan and some samples from humans. Animals studied were inoculated (infect or introduce) and the viral RNA load was quantified from organs of those euthanised and faeces of animals isolated.
“In summary, we found that ferrets and cats are highly susceptible to SARS-CoV-2, dogs have low susceptibility, and livestock including pigs, chickens, and ducks are not susceptible to the virus. Ferrets have frequently been used as an animal model for the study of human respiratory viruses Unlike influenza viruses and other human SARS-coronavirus, which replicate in both the upper and lower respiratory tract of ferrets, we found SARS-CoV-2 only replicates in the nasal turbinate, soft palate, and tonsils of ferrets,” the study published on Wednesday concluded.
Some media reports have suggested that even dogs can be infected. Bloomberg, for example, carried a report on March 19 that two dogs had tested positive for the virus in Hong Kong.
But it’s too early to draw any conclusion about which animals are reservoirs, said scientists. “Definitely some animals will be susceptible to the virus that’s how animal models are created for further research on vaccines. But to jump to the conclusion that they can infect pet owners and humans is not right. We have domestic cats in India which can be very different from the cats in China. First, we need to understand what is the spillover point to cats there. Such spillovers happen due to zoonotic interface between humans and wild animals. In the SARS epidemic, also we saw that civet cats were a reservoir of the virus. Nobody keeps civets as pets,” said Dr Nivedita Gupta, viral disease expert at Indian Council of Medical Research.
Based on genome sequence data of SARS-CoV-2 released earlier by Chinese scientists, scientists from the Department of Immunology and Microbiology at US-based The Scripps Research Institute recently said the virus cannot be a “laboratory construct” or “purposefully manipulated”, and has natural origins. The virus is believed to have jumped from bats to an intermediate host animal which may have passed the infection to humans.
