Until about 15 years ago, cats were thought not to be susceptible to human or avian flu viruses. All of that changed in 2003 when zoos in South-East Asia that kept large cats found out to their dismay what happens when you feed H5N1 infected chicken carcasses to tigers and leopards.
The following comes from a World Health Organization GAR report from 2006.
28 February 2006
Several published studies have demonstrated H5N1 infection in large cats kept in captivity. In December 2003, two tigers and two leopards, fed on fresh chicken carcasses, died unexpectedly at a zoo in Thailand. Subsequent investigation identified H5N1 in tissue samples.
In February 2004, the virus was detected in a clouded leopard that died at a zoo near Bangkok. A white tiger died from infection with the virus at the same zoo in March 2004.
In October 2004, captive tigers fed on fresh chicken carcasses began dying in large numbers at a zoo in Thailand. Altogether 147 tigers out of 441 died of infection or were euthanized. Subsequent investigation determined that at least some tiger-to-tiger transmission of the virus occurred.
In 2006, virologist C. A. Nidom of the Institute of Tropical Disease, Airlangga University demonstrated that of 500 cats he tested in and around Jakarta, 20% had antibodies for the H5N1 bird flu virus.
Findings that prompted the FAO in 2007 to warn that: Avian influenza in cats should be closely monitored.
Since then we’ve seen ample evidence that cats – including pets – can be infected with both avian and human flu viruses.
During the 2009 H1N1 pandemic we saw several reports of feline infection, and in late 2010 we saw a study (see EID Journal: Pandemic H1N1 Infection In Cats) that looked at the pathogenesis of novel H1N1 in domestic felines.
van den Brand JMA, Stittelaar KJ, van Amerongen G, van de Bildt M, Leijten LL, Kuiken T, et al. Experimental pandemic (H1N1) 2009 virus infection of cats. Emerg Infect Dis. 2010 Nov; [Epub ahead of print]
Intratracheal infection of domestic cats with pandemic (H1N1) 2009 virus resulted in mild-to-moderate clinical signs and virus replication throughout the respiratory tract that caused diffuse alveolar damage.
Pathogenic changes in the respiratory tract in cats were similar to those that occur in humans, macaques, and ferrets (7,11–13). Seroconversion of sentinel cats indicated cat-to-cat transmission.
While we saw a rare zoonotic transmission of avian H7N2 from a cat to a human in New York City in late 2016 (see EID Journal: Avian H7N2 Virus in Human Exposed to Sick Cats) – along with vigorous with cat-to-cat transmission – companion animals are far more likely to contract seasonal flu from humans (reverse zoonosis) than to give it to people.
Which brings us to a rare report this week of two fatal H1N1 infections in cats from a single household in Connecticut. Reportedly, both cats had pre-existing conditions, and the owner of the cats had recently been sick with a flu-like illness.
Details on this case can be found in two local reports:
Sadly, some in the media still insist on calling seasonal A(H1N1) `swine flu’, particularly since there really is a swine H1N1 on our radar. But I digress . . .
From PetMD we get this following:
The H1N1 variant of the influenza virus, previously known somewhat inaccurately as “swine flu”, is contagious to cats as well as to people. In addition, this virus is also known to be able to infect dogs, pigs, and ferrets. Though the spread of this particular influenza virus is no longer considered to be an epidemic of emergency proportions, it does continue to spread worldwide.
Symptoms and Types
Symptoms may range from very mild to extremely severe and some infected cats may show no signs of disease at all.
The most common symptoms seen include:
- Lack of appetite
- Runny eyes
- Runny nose
- Labored breathing
Some cats infected with H1N1 influenza have not survived, but the majority of infected cats suffer mild to moderate symptoms.
While the risks are low, you may want to reconsider the next time you are down with the flu and are tempted to curl up with a beloved pet.
For more on companion animals and flu (of all types), you may wish to revisit: