In the era of coronavirus (COVID-19), some animals have reportedly tested positive for the virus. Given the fact that scientists believe some form of animal-to-human transmission started the pandemic, it’s worth examining the landscape — and thinking of what we can do for animals.
Late in February, a 17-year-old Pomeranian in Hong Kong, whose owner had tested positive for COVID-19, tested a “weak positive” for SARS-CoV-2, the virus that causes coronavirus. Gene sequencing of SARS-CoV-2 from the Pomeranian and its owner revealed that the viral sequences were very similar. Testing of the dog in mid-March yielded negative results, and further blood analysis indicated that the dog had developed an immune response to the virus. A two-year old German shepherd, also in Hong Kong, also tested positive for the virus after its owner did. In both cases, the positive-testing dogs were essentially asymptomatic and were each quarantined with another dog; both other dogs tested negative for the virus.
In mid-March, a cat in Belgium began experiencing diarrhea, vomiting, and breathing difficulties about one week after its owner, who later tested positive, began showing symptoms of COVID-19. Not much is known about other factors that may have caused the cat’s symptoms, but the cat did test positive for SARS-CoV-2. The cat was placed in quarantine, and its symptoms had reportedly improved by 9 days after onset. On March 30th, another cat in Hong Kong, whose owner had COVID-19, tested positive for SARS-CoV-2, but this cat has thus far appeared asymptomatic.
On April 5, the United States Department of Agriculture National Veterinary Services Laboratories confirmed a positive SARS-CoV-2 test in a tiger at the Bronx Zoo in New York. Several lions and tigers at the zoo reportedly began showing signs of respiratory illness in late March, though at the time, only one tiger tested positive for SARS-CoV-2. Public health officials believe that the big cats may have become sick after exposure to an employee infected with COVID-19. Nearly 3 weeks later, four more tigers and three lions, also at the Bronx Zoo, tested positive for SARS-CoV-2. All but one of the 8 infected big cats showed mild respiratory symptoms, and all are under veterinary care and expected to make a full recovery. Thus far, no other animals at the zoo have been exhibiting clinical signs of disease.
On April 21st, two cats in separate areas of New York state both tested positive for SARS-CoV-2; these are the first pets in the United States to test positive for the virus. Both cats displayed mild respiratory illness, and both are expected to make a full recovery. For one of the cats, no individuals in the household were confirmed to be ill with COVID-19. Experts believe the cat may have been infected by an infected-but-asymptomatic family member, or by an infected person outside the home. The owner of the second cat had tested positive for COVID-19 before the cat started displaying symptoms. Another cat in the same household showed no signs of illness.
What does this mean?
Although this news may be somewhat alarming, official sources assure that this should not be a primary cause for concern. According to the Illinois University College of Medicine, “Experts believe that dogs and cats are not easily infected with this virus, and the risk of transmission to humans is negligible compared to the risk of human-to-human transmission. As of April 2, all major health organizations, including the Centers for Disease Control and Prevention (CDC), the World Health Organization (WHO), and the World Organisation for Animal Health (OIE) say that there is no evidence that a companion animal has transmitted the virus that causes COVID-19 to a person.”
Researchers in China determined from laboratory testing evidence that “SARS-CoV-2 replicates poorly in dogs, pigs, chickens, and ducks, but efficiently in ferrets and cats…via respiratory droplets.” This study has not yet been peer-reviewed and these results should be taken with a grain of salt. Only 5 cats, 5 dogs, and 8 ferrets were tested in the study (the numbers of pigs, chickens, and ducks tested were not given), making the sample size quite small to draw conclusions from. Also the tests were performed by researchers forcibly inserting the virus directly into the animals’ noses, which is very different from an animal being naturally exposed to airborne pathogens from an infected owner. While this study shows it is possible for the animals to become infected and potentially spread the virus to other animals, it provides no evidence as to whether they can transmit the virus to humans. In 2003, during the outbreak of SARS, a virus genetically similar to COVID-19, a similar study showed that cats and ferrets could be infected with the virus, but that they did not appear to play a role in spreading the disease.
The minuscule number of COVID-infected animals worldwide certainly indicates that human-to-animal transmission is quite rare. “Given that there are about 150 million dogs and cats in the United States alone, if pets could readily catch COVID-19, we would be seeing tons of cases by now,” says Shelley Rankin, a microbiologist at the University of Pennsylvania School of Veterinary Medicine. “Yet nobody is reporting a spike in respiratory infections in cats and dogs.” As for animal to human transmission, although the SARS-CoV-2 virus is thought to initially originate from bats, many official sources, including the World Health Organization, the U.S. Centers for Disease Control and Prevention, the World Organization for Animal Health, the World Small Animal Veterinary Association, and a number of prominent researchers insist that there is no evidence to indicate that pets are passing the virus to human owners. The CDC also emphasized that conducting animal testing does not reduce the availability of tests for humans – they are different types of tests, analyzed in different laboratories – but they do not recommend the routine testing of animals at this time, given the small number of reported cases of illness.
Sadly, despite this lack of evidence for animal to human transmission, widespread fear and misinformation has led pets to become scapegoats in many parts of China. According to Time Magazine, thousands of pets are being abandoned, intentionally or due to harsh travel restrictions, and some have even been killed by their owners under the misguided fear that the animals are spreading the virus. Time Magazine reports that the pet crisis is particularly bad in Hubei province, where the virus is suspected to have infected the first human in the province’s capital city of Wuhan. According to a Time Magazine interview of a volunteer at the Furry Angels Heaven animal charity in Wuhan, “when a person in Wuhan is found to have COVID-19 then the authorities kill all animals in the home as a precaution.” Stray animals found on the streets are routinely rounded up and euthanized. Furthermore, extremely strict travel regulations have been put in place in Hubei. Thousands of pet owners who expected to be away for just a few days over the Lunar New Year have now been unable to return home for weeks. Time Magazine reported that many owners have been begging strangers to break into their homes to feed and care for their abandoned pets. Some locals have been breaking the law by taking in numerous abandoned animals, and some policemen are even in cahoots — tipping off the rescuers before a raid so that the animals can be hidden — but the situation remains dire.
What you can do
Officials say that, although there is little to no reason to fear pets transmitting COVID-19, this is a time to be careful. According to the Cornell School of Veterinary Medicine, “If you notice your pet experiencing respiratory illness or fever, we recommend (out of an abundance of caution) to quarantine them, wash your hands carefully before and after handling them, and contact a veterinarian immediately to consult about best next steps.” The World Organization for Animal Health also suggests that, as a precautionary measure, “animals belonging to owners infected with COVID-19 should be kept indoors as much as possible and contact with those pets should be avoided as much as possible.”
The Centers for Disease Control recommends using proper hygiene practices when interacting with your pet. They advise that people should not let their pets interact with people or other animals outside the household. Cats should be kept indoors when possible, and dogs should be kept away from dog parks and crowded areas; owners should attempt to maintain at least 6 feet between their dog and other people and animals.
If you are sick with COVID-19, you should “restrict contact with pets, just as you would restrict your contact with other people. Avoid snuggling, being kissed or licked, and sharing food. If you must interact with your pet, wash your hands before and after, and wear a face mask.”
On April 29, New York City’s Emergency Management Department and the Mayor’s Office of Animal Welfare announced the launch of the NYC COVID-19 Pet Hotline, the first of its kind, to provide support for people and their pets during this time. Hotline responders will answer questions and concerns about keeping pets safe from COVID-19, and will also be able to connect callers to pet-related resources, such as subsidized emergency veterinary care, and food and supply distribution services. The hotline can be reached at 1-877-204-9921, and is open from 8:00am to 8:00pm, 7 days a week.
The United States Department of Agriculture is keeping track of cases of SARS-CoV-2 in animals in the United States that have been confirmed by the USDA’s National Veterinary Service Laboratories. They can be viewed here.