pets that spend time outdoors and probably caught it while hunting sick rodents or wild birds.
Now, a small but growing number of domestic cats have become sick with H5N1, the strain of bird flu responsible for the current outbreak in the United States, after eating raw food or drinking unpasteurized milk. Some of these cats died.
The strain of avian influenza currently circulating is not adapted spread effectively among people. There have been no known cases of cat-to-human transmission of the virus during the current H5N1 outbreak.
However, there is always been risk that catswhich perhaps only semi-domesticated, can bring home illness from a midnight walk.
“Companion animals, and especially cats, pose a 100% threat to public health in terms of the risk of zoonotic transmission to humans,” the virologist said. Angela Rasmussen, Ph.D.who studies disease progression of new viruses at the University of Saskatchewan. Organization for Vaccines and Infectious Diseases.
This is because we snuggle with our cats and sleep in bed with them. When we're not looking, cats drink water from our glasses and walk on the kitchen counters. So, cat owners should be aware of the ongoing spread of bird flu. “TO reducing the risk for your catsyou reduce the risk to yourself,” Rasmussen said.
Rasmussen doesn't think pet owners should be afraid of their cats giving them bird flu, but says taking precautions is good for both pets and public health.
Signs of bird flu in cats include a runny nose and discharge around the eyes, scientists explained. Michael K. Bailey, DVM, president-elect American Veterinary Medical Association.
H5N1 also causes neurological problems such as dizziness and seizures, which are also symptoms of rabies. Rabies is almost always fatal and poses a threat to human health, so any animal suspected of having the viral disease must be euthanized. Bailey encourages people to make sure pets are up to date on vaccinations.
Vet Jane Sykes, Ph.D.who specializes in infectious diseases of cats and dogs at the UC Davis School of Veterinary Medicine, says people shouldn't assume it's avian flu if their cat is sick—even if their pet spends time outdoors or eats raw food. Upper respiratory disease is common in cats, while the H5N1 virus is “still quite rare.”
Sykes only feeds her indoor cat, Freckles, regular food. She said NPR And KFF health news she's not worried about Freckles getting H5N1 because the heating process of making dry or canned pet food kills viruses.
More cases in cats, more risk for people
Some people feed their pets raw meat or unpasteurized milk because they believe it is a more nutritious and natural diet. American Veterinary Medical Association website prevented by foodborne pathogens like salmonella and listeria, and now highly pathogenic H5N1.
By keeping pets healthy, veterinarians play an important role in protecting people from zoonotic diseases. The American Veterinary Medical Association says the risk of transmission of the H5N1 virus from pets to humans “is considered extremely low, but not zero.”
State and local health authorities, including Los Angeles County And Washington stateissued similar warnings against raw feeding of pets.
Concern for human health is part of the reason the F.D.A. announced last month cat and dog food companies are now being asked to update their safety plans to protect against bird flu.
This comes after the Oregon Department of Agriculture discovered a cat that was “pure domestic cat” contracted H5N1 and died after eating a frozen turkey product produced by a raw pet food brand. Northwest Naturals. It said that “tests confirmed a genetic match of the virus in raw and frozen pet food and the infected cat.”
Northwest Naturals has voluntarily recalled this lot of its frozen turkey product. The company told KFF health news And NPR that the recall involved a “small quantity of product” and that the company had concerns about the accuracy of testing conducted by the Oregon Department of Agriculture.
The Los Angeles County Department of Public Health said five cats from two households tested positive for avian influenza after drinking unpasteurized raw milk from Raw Farm, a dairy farm in California's Central Valley.
Raw material farm voluntarily withdrawn its milk and cream after retail products tested positive for H5N1, but denies any food safety issuescalling the concern a “political issue.”
Veterinarians are also warning pet owners not to leave cats unattended outdoors as there is a risk of contracting H5N1 through interaction with other animals that may carry the disease.
“This is a very scary virus, given that it can infect so many different host species,” he said. Bruce Kornreich, DVM, Ph.D.Director of the Cornell University Center for Feline Health.
At least one case of a human contracting avian influenza from a cat occurred in 2016. NPR reportedA veterinarian in New York contracted the virus after close contact with infected cats. The vet experienced mild symptoms and recovered quickly.
In this case, the bird flu strain was H7N2, not H5N1, which is currently circulating in the United States.
Sykes explained that H7N2 is a completely different type of virus. But she said it shows that transmission of bird flu from cats to humans is theoretically possible.
There isn't much research on the transmission of avian flu from pets such as cats or dogs to humans, although Rasmussen agreed it was definitely a concern: The more infections animals have, “the more your luck will potentially run out.”
Most people infected with H5N1 are agricultural workers who have had direct contact with infected poultry or cattle. At least 67 confirmed human cases of H5N1 have been reported in the United States one dead in a person with a weakened immune system who has had contact with birds.
Overall, zoonotic disease researchers want more H5N1 monitoring in companion animals of all types. Even if the number of human deaths from H5N1 remains relatively low, it remains a public health risk.
Chances of mutation
Part of the concern about the H5N1 outbreak is that avian influenza viruses are changing. Just a few mutations can make this strain can spread between people. And the more people become infected with H5N1, the more likely it is that it will adapt and become more effective, he says. Suresh Kuchipudi, PhD, MVSc, is a virologist at the University of Pittsburgh School of Public Health, where he researches zoonotic diseases. Kuchipudi studied H5N1 in cats.
Another problem is what is called reassortment. If an animal or person is infected with two viruses at once, the viruses can exchange genetic material to create something new. This is common with influenza, so virologists are looking for a case where avian influenza reassorts to form a virus that is much more contagious and potentially more virulent.
Virologist Rasmussen is much more concerned about this happening in pigs. The physiology of human breathing is more similar to that of pigs than of cats. At this time, the current H5N1 outbreak has not reached commercial pig production facilities. Rasmussen hopes it stays that way.
Kuchipudi said that recombinations are a relatively rare phenomenon, but the outcome is completely unpredictable. Sometimes the results are favorable, although it was most likely recombination involving an avian virus that led to the 1918 influenza pandemic, which killed one animal. about 50 million people. A century later, virologists created a global surveillance network to monitor influenza viruses. Scientists say continued investment in this network is key to prepare for and hopefully prevent another pandemic.
Winter is “reassortment season” as all the flu viruses circulate, Rasmussen said. Recombination of cats is technically possible because these pets I sometimes get the seasonal flubut this is very unlikely. Rather, Rasmussen says, it's more likely that a cat will transmit H5N1 to a person who already has seasonal flu, and then the sick person will reassort. While the risk is not zero, Rasmussen doubts that will happen. This will depend on how sick the person is and how much of the virus they were exposed to from their cat.
“Unless the cat is really shedding a ton of virus and you're kind of kissing the cat, I think it would be difficult,” she said.
Rasmussen and Kuchipudi caution that there is not enough research to know exactly how much virus cats shed or even how they shed the virus.
Center for Disease Control and Prevention (CDC) was ready to release new study of H5N1 in cats, but it was delayed when the Trump administration suspended the study. Weekly Morbidity and Mortality Report. This investigation was revealed through emails received by KFF health news found in a public records request these domestic cats probably contracted bird flu from dairy farm workers.
Scientists and public health authorities must question previous assumptions about bird flu, Kuchipudi urged. He noted that 20 years ago no one would have imagined that avian influenza would infect dairy cattle as much as it does now.
Dogs seem to be doing better
FDA says other pets, including dogs, can become infected with avian influenza. There are no confirmed cases of H5N1 in dogs in the United States, although dogs have died from the virus in other countries.
There is some controversy and a complete lack of research about whether the biology of cats makes them more susceptible to H5N1 than other mammals, including humans, pigs and dogs.
But cats' behaviors, such as their love of dairy products and predation on wild birds, put them at higher risk, Kuchipudi said. Additionally, group living may play a role, since there are more feral cat colonies in the United States than stray dog packs.
There is little humans can do about the H5N1 virus circulating among wild birds. As Rasmussen explained: “It flies through the sky. It migrates north and south depending on the time of year.”
But she said there is a lot people can do to keep the virus out of their homes.
This includes limiting pets' exposure to H5N1, not feeding them raw food or unpasteurized milk, and trying to prevent them from interacting with animals such as rodents and wild birds that may be infected with the virus.
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