Iowa cat tests positive for H1N1 virus

First known feline case; role in transmission undetermined

Published: November 04, 2009
By Jennifer Fiala

Health officials in Iowa announced today that H1N1 pandemic virus has been confirmed in a 13-year-old indoor cat. It is the first known case of a cat contracting the virus in the United States. 

The cat was presented to Lloyd Veterinary Medical Center at Iowa State University (ISU) on Oct. 27 with symptoms of malaise and depression and was released the same day with standard care instructions and antibiotics to treat any secondary infections. 

Clinicians at the teaching hospital decided that the cat should be tested for H1N1 virus after its owner confirmed that three members of the household had experienced flu-like symptoms prior to the cat's illness, although whether they suffered from H1N1 is not yet known. While the Veterinary Diagnostic Laboratory at ISU made the initial identification, a number of agencies, including the United States Department of Agriculture and the Iowa Department of Agriculture and Land Stewardship's Animal Industry Bureau reportedly confirmed the strain as 2009 H1N1 influenza. 

Dr. Brett Sponseller, ISU assistant professor of Veterinary Microbiology and Preventative Medicine, explains that H1N1 infections among people are common in the area. 

"The cat is alive and doing well. It's not terribly surprising (that the cat contracted the virus) just knowing that influenza crosses species lines regularly," he says. 

While those in the veterinary profession might consider such a case inevitable, news of it has quickly made the rounds among popular media outlets. Sponseller says calls have flooded his office since the Iowa Department of Health released a public statement today advising owners to contact their veterinarians if their pets exhibit signs of respiratory illness. 

The American Veterinary Medical Association (AVMA) also issued a press release stating there are no indications that cats serve as a vector for the virus, which has also surfaced in pigs, birds and ferrets. The group is attempting to track all confirmed cases of H1N1 in animals and is posting updates to a public health section of its Web site

Whether or not cats can transmit the virus to humans is unclear. Dr. Edward Breitschwerdt, a professor of Medicine and Infectious Disease at North Carolina State University's College of Veterinary Medicine, believes that in rare instances, they can. 

Breitschwerdt surmises that the viral load in a cat's nasal passages might not be great enough to infect a human or a cat's sneeze might not be powerful enough to spread the virus to its owners. 

"I don't think there's any question that a cat can be infected, but there's no evidence that a cat can transmit the virus to humans," he says. "But I guarantee you that if I thought my cat had H1N1, it would not be sleeping in the bed with me. I can't imagine that it's not potentially infectious." 

Dr. Tony Johnson, a Veterinary Information Network (VIN) consultant and clinical assistant professor at Purdue University's veterinary school, has doubts that he'll ever come across an H1N1-infected cat. In fact, without seeing more details on methods used to test the sample in Iowa, he's not totally convinced that the  laboratory reports are accurate. 

"Honestly, it's going to be a little like the tainted food thing," he predicts, referring to the pet food scandal of 2007 that involved melamine contamination. "There's going to be so much hysteria that actually finding out which patients have it will be clouded by all the panic. Owners will be wringing their hands." 

Johnson adds that although Purdue's teaching hospital receives a number of cats experiencing respiratory illnesses, when it comes it H1N1, "everything would have to line up for me to want to test for it." 

Still, identification of a cat infected with the current H1N1 strain is a significant finding and a reminder of the importance of monitoring these highly changeable viruses, says Dr. Miranda Spindel, a VIN consultant and director of Veterinary Outreach for the American Society for the Prevention of Cruelty to Animals. 

"Continued monitoring will help elucidate what role cats may play in hosting and transmitting H1N1," she says, reiterating that "presently there is no evidence that cats can transmit the virus to other cats or to humans once infected." 

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