In early April of 2020, the revelation that coronavirus can be transmitted from humans to animals in the United States was made by the Bronx Zoo in New York City. Previous to this case, the coronavirus was believed to only be a threat among humans. Animals were not thought by scientists to become ill from the disease via human transmission. It seems as if, once again, the coronavirus surprises health officials with a new challenge and continues to pose a greater threat to the public. (1)

Tiger Tests Positive

A four-year-old Malayan tiger named Nadia is the first case of an animal to be infected with COVID-19 in the US. The test was read by the National Veterinary Services Laboratory in Iowa. The Bronx Zoo, which has been closed to the public since March 16th, believes Nadia was infected by an asymptomatic zookeeper. The zookeeper and details of contact with the tiger remain unidentified.

Initially, Nadia had symptoms like dry cough and decreased appetite that pointed her caretakers towards testing for the virus (around March 27th). But they were reluctant – as there had been no previous cases of an animal getting sick from the virus. Worldwide, isolated household pets have tested positive for the virus, but no evidence that they were unwell. (1)

“This is the first time that any of us know of anywhere in the world that a person infected the animal and the animal got sick,” Paul Calle, the chief veterinarian at the zoo, told news outlets on Sunday, April 5th. The Bronx Zoo also intends to reach out to other zoos to help reduce the risk of transmission to other animals in captivity. Though other big cats became sick around Nadia, the zoo will likely not test due to the risks posed by anesthesia needed to perform the swab. (2)

Zoo Animals Practice Social Distancing

Currently, Nadia and the six other big cats showing symptoms are in isolation at the Bronx Zoo’s Tiger Mountain area. Nadia remains the illest, but all are being closely monitored. The group is expected to make a full recovery. And, beyond some mild symptoms, they “are otherwise doing well under veterinary care and are bright, alert, and interactive with their keepers.” (1)

If the virus reaches other animals, it is unknown how the different species will react. Going forward, the zoo plans to put in new policies and protocols to protect both animals and staff. Officials at the Bronx Zoo have assured that protecting everyone from the virus, now that they know this is a possibility, is key to their daily operations.

“We tested the cat [Nadia] out of an abundance of caution and will ensure any knowledge we gain about COVID-19 will contribute to the world’s continuing understanding of this novel coronavirus,” said zoo officials. (1)

What About My Pets?

The Centers for Disease Control and Prevention (CDC) maintains that the infection of animals with COVID-19 is still rare. Animals that have tested positive were at notable epicentres of coronavirus outbreaks. More studies will hopefully reveal the full extent of risk to animals and humans with this emerging infection. The Words Health Organization (WHO) is already undertaking such measures. (3)

From an article produced by the BBC, Dr. Sarah Caddy shared her thoughts on the transmission of COVID-19 to a tiger. As a veterinarian and research fellow at the University of Cambridge, she said, “It is surprising that the tiger has become infected with what must have been a fairly low dose of virus – we can assume the tiger did not have continual close contact with the asymptomatic zookeeper”. However, she stands by the CDC’s assertions that the rate of transmission should still be low among most species of animals. High risk species for COVID-19 transmission are thought to be primates like gorillas and orangutans. (1)

In the meantime, to protect yourself and the animals in your life continue to practice good hand washing. Wash your hands after contact with any animal or person. If you feel unwell, limit contact with your pet or livestock. Keep your pet clean and promote proper hygiene of them (even if the groomer is closed!). Finally, never stray away from talking to your veterinarian. Your pet’s medical team will be able to guide you during this difficult time. (3)