#18,150
In today's update from the USDA, 5 more domestic cats (4 in Texas, 1 in Minnesota) have been added to the list of H5N1 infected mammals, along with with 2 raccoons, 1 striped skunk, and a red fox. For the first time in 3 weeks no additional mice were added to the list.
While the total number of infected mammals in the United States now sits at 327, this is undoubtedly a massive undercount, as many states aren't actively looking, and many animals die in remote places and are never tested.
We've known for two decades that large cats in captivity (when fed infected poultry) can contract HPAI H5N1 (see 2004 CIDRAP Report), and we've seen scattered reports of dogs and cats infected with the virus (see 2015's HPAI H5: Catch As Cats Can) in the years since.
But since the emergence of a new, more transmissible H5N1 virus in 2021, the number of companion animals (and other mammals) reported to be infected has risen sharply.
Infections have ranged from asymptomatic (in dogs and cats in Italy) to severe and often fatal in other countries (see Preprint: Avian Influenza Virus Infections in Felines: A Systematic Review of Two Decades of Literature).
Despite this steep increase in reports, it is likely that many cases have gone unreported.
While the risks to humans from H5N1 remains low, the CDC offers the following advice for pet owners.
Pet OwnersIf your domestic animals (e.g., cats or dogs) go outside and could potentially eat or be exposed to sick or dead birds infected with bird flu viruses, or an environment contaminated with bird flu virus, they could become infected with bird flu. While it's unlikely that you would get sick with bird flu through direct contact with your infected pet, it is possible. For example, in 2016, the spread of bird flu from a cat to a person was reported in NYC. The person who was infected [2.29 MB, 4 pages] was a veterinarian who had mild flu symptoms after prolonged exposure to sick cats without using personal protective equipment.
If your pet is showing signs of illness compatible with bird flu virus infection and has been exposed to infected (sick or dead) wild birds/poultry, you should monitor your health for signs of fever or infection.
How to prevent spread
As a general precaution, people should avoid direct contact with wild birds and observe wild birds only from a distance, whenever possible. People should also avoid contact between their pets (e.g., pet birds, dogs and cats) with wild birds. Don't touch sick or dead birds, their feces or litter, or any surface or water source (e.g., ponds, waterers, buckets, pans, troughs) that might be contaminated with their saliva, feces, or any other bodily fluids without wearing personal protective equipment (PPE). More information about specific precautions to take for preventing the spread of bird flu viruses between animals and people is available at Prevention and Antiviral Treatment of Bird Flu Viruses in People. Additional information about the appropriate PPE to wear is available at Backyard Flock Owners: Take Steps to Protect Yourself from Avian Influenza.
People Who Have Had Direct Contact with Infected or Potentially Infected Animals
During outbreaks of bird flu in wild birds and/or poultry, people who have had direct contact with infected or potentially infected animals, including sick animals that might have eaten bird flu-infected birds, should monitor their health for fever and symptoms of infection.
Signs and Symptoms may include:
*Fever may not always be present
- Fever (Temperature of 100°F [37.8°C] or greater) or feeling feverish/chills*
- Cough
- Sore throat
- Difficulty breathing/Shortness of breath
- Conjunctivitis (eye tearing, redness, irritation, or discharge from eye)
- Headaches
- Runny or stuffy nose
- Muscle or body aches
- Diarrhea
Call your state/local health department immediately if you develop any of these signs or symptoms during the 10-days after your exposure to an infected or potentially infected animal. Discuss your potential exposure and ask about testing. If testing is recommended, isolate as much as possible until test results come back and/or you have recovered from your illness.
Additionally, close contacts (family members, etc.) of people who have been exposed to a person or animal with lab-confirmed bird flu viruses should also monitor their health for 10 days after their exposure for signs and symptoms of illness. If close contacts of people who have been exposed to H5 bird flu viruses develop signs and symptoms of illness, they should also contact their state health department.