A new study has confirmed the transmission pathway between humans and their feline companions. This study provides the strongest clinical evidence to date of the transmission of COVID-19 between the two species.
Building on anecdotal accounts since 2020, the new study looked in detail at the possibility of viral transmission between cats and their owners. However, the transmission appears to only go one way — from humans to cats.
The study was published in the journal VetRecord, and looked at two cases of domestic cats with a respiratory illness that later proved to be SARS-CoV-2 infections. Sadly, one of the subjects needed to be put down because of its infection.
By using genomic analysis, the research team was able to show that the viral strain had no “cat-specific mutations,” and therefore, can only have come from humans originally. Specifically, the genetic makeup of the virus was very similar to the prevalent strain in the UK at the time of the study.
"These findings indicate that human-to-cat transmission of SARS-CoV-2 occurred during the COVID-19 pandemic in the UK, with the infected cats displaying mild or severe respiratory disease,” explained the study’s lead author Margaret Hosie. “Given the ability of the coronavirus to infect companion animals, it will be important to monitor for human-to-cat, cat-to-cat, and cat-to-human transmission.”
There is still no evidence of the virus spreading between cats and humans
This study also builds on accounts of the virus spreading to zoo animals.
“There is a growing international body of literature that is suggesting that asymptomatic transmission to pet dogs and cats from human patients may take place more commonly than disease is seen in the animals,” said James Wood from the University of Cambridge. “Careful monitoring of the health of animals in contact with human patients is warranted and owners should follow advice, where possible, to try to separate themselves from their animals when they are clinically unwell.”
The findings are interesting, but may also reveal a potential threat for future mutations of the virus in animal populations.
“While this paper does not look at transmission, this raises the possibility that virus variants could be more infectious for other species including cats and dogs which could possibly play a role in animal reservoirs and pose a risk of spill over back into humans,” explained Lawrence Young, from the University of Warwick.
This concern has led other researchers to look for ways to safely vaccinate animals, as well as humans. In fact, in March of this year, Russia announced the world’s first COVID-19 for animals. At present, there are no official plans of similar programs in place like the UK, but experts stress the need for heightened surveillance of the virus in animals.
Eleanor Riley, an infectious disease expert from the University of Edinburgh said on the matter, “it is vitally important to monitor SARS-CoV-2 infections in animals, both domesticated and free-living, as they offer a potential reservoir for virus persistence, mutation, and re-emergence into the human population.”
The results of this study are intriguing, but with no confirmed viral transmission between pets and their owners, pet owners should not unduly worry.
The original study was published in the journal VetRecord.