UW scientists identify flu strain sickening shelter cats

Scientists at the University of Wisconsin-Madison recently identified the influenza strain behind a flu outbreak among cats in a New York City shelter. The rare subtype previously was not found in domestic felines.

Cats that have contracted the strain in the shelter have displayed upper-respiratory symptoms such as runny nose, congestion, persistent cough and lip smacking, but the illness has not been severe.

No other species of animals from the shelter, including dogs, has tested positive for the virus.

“While we are concerned about this new infection, the cats are experiencing only mild to moderate illness, but a few have developed pneumonia,” says Sandra Newbury, clinical assistant professor at the veterinary school and director of the UW Shelter Medicine Program.

She added, “Many of the cats who were initially ill are already recovering. We do want people to be aware of what is happening, but influenza infection is unlikely in cats that have not had contact with cats from New York City’s Manhattan Animal Care Center.”

First time infection of cats

The first cases of influenza at the shelter were reported in late November when a private company, IDEXX Reference Laboratories, tested sick cats housed at ACC-Manhattan.

The shelter then approached the UW Shelter Medicine Program and the Wisconsin Veterinary Diagnostic Laboratory for more assistance. Both had helped manage outbreaks of a different strain of influenza that affected dogs and cats in the Midwest earlier this year and in 2015.

Testing revealed that the virus responsible was low pathogenic avian influenza H7N2.

Further testing at two other laboratories found additional positive samples and confirmed the identification of the strain.

“This is the first time H7N2 has been detected and transmitted among domestic cats,” said Kathy Toohey-Kurth, clinical professor and head of the Wisconsin Veterinary Diagnostic Laboratory’s virology section.

Several cases of H7N2 were found in commercial poultry in the United States between 2000 and 2006 and it may be able to spread to other animals besides cats.

Low risk for cats — and humans

The virus is thought to pose low risk to people. To date, there have two cases of H7N2 found in humans — both ending with full recovery.

While influenza infection is unlikely in cats that have not had contact with infected felines from the shelter, owners whose animals show signs of influenza should contact their veterinarian for instructions.

Cats suspected to be infected with the virus should be housed separately from other animals and precautions should be taken to prevent spread of the virus on hands and clothing.

“We’ll continue to work with the shelter to help manage the case and offer testing to any cats in rescue groups that are affected,” UW Shelter Medicine Program’s Newbury said. “We are hoping that offering this kind of diagnostic support will help rescue groups identify if they have cats with the virus so they can isolate them in order to stop the spread.”

Diagnostic testing for animals that have come from the New York City shelter since Nov. 12 was paid for by Maddie’s Fund, a family foundation that seeks to “revolutionize the status and well-being of companion animals.”

On the Web

Shelters and rescue groups may contact the UW Shelter Medicine Program at with testing inquiries or questions regarding influenza in cats and dogs. They can also look for updates at uwsheltermedicine.com.