Cats Get Avian Flu in New York City Shelter

Are New York City cats getting the dog flu? While there are isolated instance of dogs sharing their H3N2 canine influenza with cats, it’s thought to be a very rare event. However, veterinarians and other public health expects became concerned when 45 cats at animal care and control in Manhattan, NY came down with flu.

Dr. Sandra Newbury, clinical assistant professor and director of shelter medicine at University of Wisconsin College of Veterinary Medicine, Madison says, “Cats in shelters unfortunately get sick all the time with upper respiratory issues. So, first it was important to confirm this is really the flu.”

It turns out it is the flu. However, testing dogs at the Manhattan shelter, none tested positive for canine influenza. The mystery grows – so it seemed unlikely to be that cats are getting canine influenza after all. And it turned out they are not.

The New York City Health Department and the Animal Care Centers of NYC (ACC) announced today (December 15) that a strain of influenza A virus, known as low pathogenic avian influenza H7N2, has been identified in the 45 cats housed at the Manhattan shelter. This is the first time this virus has been detected and transmitted among domestic cats.

How the heck did the cats or at least one cat come down with this virus? No one has a clue.

So far this virus causes mild illness in most of the cats and is thought to pose a low risk to humans. There have been only two documented human cases of low pathogenic avian influenza H7N2 infection in the United States – one in a farmer who worked closely with chickens in 2002 and the other with an unknown source in 2003. Both these patients recovered.

Based on recent testing data by the University of Wisconsin, November 12, 2016 is the earliest date when this virus was likely introduced into the shelter. The Health Department is contacting all persons who have adopted cats from ACC’s Manhattan care center since November 12th. The Health Department is advising persons who adopted Manhattan shelter cats during this period to call the Department at 866-692-3641 for care instructions, including keeping their cat separated from other cats or animals, if their cat is showing signs of persistent cough, lip smacking, runny nose, and fever. The Health Department is also advising these pet owners to call 866-692-3641 if they develop fever with a sore throat, fever with a cough, or red, inflamed eyes. 

It’s apparent, this influenza virus is spreading from cat to cat and may be able to spread to other animals and possibly even humans. No human infections have been identified to date, or in any other species. So far, ACC has tested 20 dogs at the shelter, and none have contracted this virus. Testing of other animals, including rabbits and guinea pigs, is ongoing. There have been no reported cases of this virus among cats outside of the ACC shelter system.  And considering people had lots of exposure with these sick cats, and none have come down with the flu seems to support the notion that this flu is not likely make people sick. 

ACC will continue to distribute instructions to all new and recent cat adopters to monitor their cats, which includes guidance on checking animals for upper respiratory illness. The Health Department is coordinating closely with the Centers for Disease Control and Prevention (CDC), the US Department of Agriculture, the University of Wisconsin-Madison, and community partners.

“Although this strain of the avian flu has only resulted in mild to moderate illness in some cats located in one shelter, we have begun to test staff and people in close contact with the cats out of an abundance of caution,” explained First Deputy Health Commissioner Dr. Oxiris Barbot in a press release. “We will continue to actively monitor all people involved and adapt our response accordingly.”    

Newbury told me the situation is “quite unusual.”

She recalled that in how an equine flu jumped to dogs. Canine influenza H3N8 virus originated in horses, has spread to dogs, and can now spread between dogs. The H3N8 equine influenza (horse flu) virus has been known to exist in horses for more than 40 years. In 2004, however, cases of an unknown respiratory illness in dogs (initially greyhounds) were reported in Florida. An investigation showed that this respiratory illness was caused by the equine influenza A H3N8 virus. Scientists believe this virus jumped species (from horses to dogs) and has adapted to cause illness in dogs and spread among dogs, especially those housed in kennels and shelters. This is now considered a dog-specific H3N8 virus. In September 2005, this virus was identified by experts as a “newly emerging pathogen in the dog population” in the United States.

“While we are concerned about his new infection, the cats are experiencing only mild to moderate illness, other than one older cat who developed pneumonia,” said Newbury. “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 who have not had contact with cats from New York City’s Manhattan Animal Care Center.” 

Most of the infected cats have had a mild illness. One infected cat, who had underlying health problems and advanced age, died.  The Health Department and ACC are working to identify a quarantine facility while the Manhattan shelter is disinfected. The cats will be monitored and released from quarantine once they have all fully recovered.

This is a reminder of what the flu virus can do (in any species). And a reminder what we can do – for people or dogs: Vaccinate (as a physician or veterinarian) suggests. One difference is dogs can’t talk to one another about the flu. Where dog flu exists at all or has existed, dogs being boarded, kenneled, in daycare or at all social should be considered candidates for the vaccine. A new vaccine includes both strains of canine influenza virus in one shot (and booster), H3N2 and H3N8, (To be clear you don’t vaccinate cats with a dog flu vaccine).

While this influenza infection is very unlikely in cats who have not had contact with cats from the ACC shelter, owners whose animals show signs of influenza should contact their veterinarian for care instructions and hand washing precautions should be taken to prevent spread of the virus on hands and clothing.

The Health Department will be coordinating testing and care for ACC employees and volunteers, though it’s important to note – so far, nothing has turned up. 

The Health Department will be releasing guidance to veterinarians about how to evaluate cats suspected of being infected with this virus and guidance to physicians about how to evaluate humans who have been exposed to cats suspected of having this virus.

The Wisconsin Veterinary Diagnostic Laboratory made the initial identification of the strain and the U.S. Department of Agriculture’s National Veterinary Services Laboratory confirmed the test results.

Kathy Toohey-Kurth, at The Wisconsin Veterinary Diagnostic Laboratory, working with the University of Wisconsin-Madison Shelter Medicine Program, made the initial identification of the strain and the U.S. Department of Agriculture’s National Veterinary Services Laboratory confirmed the test results. The University of Wisconsin-Madison Shelter Medicine Program continues to work with ACC Manhattan shelter to manage the illness.