While not currently viewed as posing a serious human health threat, the discovery of avian H7N2 circulating in dozens of cats at a New York City animal shelter last week is nonetheless important - both for its scientific interest - and for its potential to spread in the feline population.
As we discussed two days ago, up until 2004 dogs were considered pretty much immune to flu - then Equine H3N8 jumped species at a racetrack in Florida, followed three years later by an avian H3N2 jumping to dogs in South Korea.
A similar event with felines - particularly with an avian virus that has shown some (minor) ability to infect humans, and a greater ability to infect poultry - could present some serious challenges.
Long time readers may recall that back in 2007, in Cat Got Your Virus?, we looked at the work of Dr. C.A. Nidom of Airlangga University in Surabaya, who discovered H5N1 antibodies in 20 percent of 500 stray cats near poultry markets in four areas of Java between September and December of 2006.
Whether cats played a role in the spread of H5N1 remains a matter for conjecture, but a 20% seroprevalence suggested the virus was spreading easily among them.
LPAI H7N2 is a far cry from HPAI H5N1, but it - like many other LPAI H5 and H7 strains - is believed capable of mutating into an highly pathogenic strain, and is therefore viewed as a serious threat to the poultry industry.
On Thursday we also learned that one veterinarian working with infected cats in NYC had been mildly infected, and that the number of cats infected had grown to over 100, across multiple shelters.
Today we learn that some cats may have been transferred from affected NYC shelters to those in Pennsylvania, and they may have possibly been exposed to the virus.
The plot, as they say, thickens. . .
12/23/2016State Veterinarian Recommends Hand-Washing Following Exposure to Quarantined Cats
Harrisburg, PA - Veterinarians at Pennsylvania’s Department of Agriculture have confirmed that almost a dozen cats that may have been exposed to an avian-type influenza virus in New York City shelters have been placed in special quarantine in one of three animal shelters in Chester County.
The low-pathogenic influenza virus does not pose a health hazard to people, according to the Pennsylvania Department of Health, however, health officials reminded citizens to wash their hands thoroughly and exercise precautions recommended during flu season--especially for those people who may have come into contact with the quarantined cats that originated from the New York shelters or were exposed to cats from these shelters.
The Agriculture department is involved because the North American H7N2 virus has been sequenced and is reportedly identical to the virus found in turkeys and chickens in Pennsylvania and Virginia during the 2002-2003 winter season.
“The cats we're testing and monitoring were transferred last month from an animal shelter in New York before some of the cats developed symptoms similar to a head cold or mild case of the flu.
The cats have a low-pathogenic variety of the avian influenza virus,” explained State Veterinarian Dr. David Wolfgang. “Fortunately, we have no indication that any poultry flocks have been exposed to an infected cat.”
There have been no reports of infected cats spreading the virus to other species, nor has the department received any information to suggest that the virus is causing any human illness, even among people in close contact with the cats.
The sick cats are being treated and are expected to recover fully. In the meanwhile, the Agriculture department has placed quarantines on three shelters in Chester County and has recommended that cat adoptions from those shelters should be postponed until further notice.
The Agriculture department is working with the three shelters to obtain records of any cats leaving these shelters since mid-November, when the affected cats were diagnosed.
Representatives from the Agriculture department will contact anyone who has adopted or fostered cats from these shelters.
“During our outreach to those who have adopted or fostered any cats from these shelters, we ask whether they have backyard poultry or contact with commercial poultry flocks. If so, we will follow our normal avian influenza protocols, which involves treating the poultry as potentially exposed to avian influenza,” Wolfgang explained. “We would quarantine the poultry and test samples at least 14 days after the cat(s) arrived in the home.”
For the latest information on avian influenza, visit The Department of Agriculture’s Animal Health and Diagnostic Services page at AHDServices. http://www.agriculture.pa.gov/Protect/AHDServices/avian_influenza/Pages/default.aspx ">AHDServices.>
MEDIA CONTACT: Bonnie McCann - 717-783-0133
Given the rate with which flu viruses evolve, the statement that `the North American H7N2 virus has been sequenced and is reportedly identical to the virus found in turkeys and chickens in Pennsylvania and Virginia during the 2002-2003 winter season' is pretty remarkable.
While the number of human infections with H7N2 (that we know of) can be counted on one's hands, and all of those were mild, the more opportunities the virus has to infect humans, the greater the chances it will adapt to human physiology.
Should H7N2 become endemic in cats, as H3N8 and H3N2 have in dogs, that could have some serious ramifications. Companion animals would make an ideal vector to expose a lot of humans to a novel virus.
All of this is very preliminary, and likely even premature, since we have no evidence that the virus is circulating outside of these animal shelters. If, on the other hand, other cats start turning up at vets with the virus who had no contact with these shelters, then this becomes a much bigger story.