The current outbreak, which began with dairy cattle infections in March 2024, has resulted in more than 130 confirmed cases in domestic cats across multiple countries.
Lessons from Early Outbreaks on Cats
The early recognition of H5N1 in cats provided several critical insights that continue to inform current management strategies. First, cats demonstrated exquisite sensitivity to H5N1 infection, with even small viral doses capable of causing severe disease.
Second, the high case fatality rate in cats (approaching 70% in early studies) emphasized the severity of H5N1 infection in this species and the need for aggressive prevention measures. The historical foundation established by these early studies continues to inform current understanding and management of H5N1 in cats, providing the scientific basis for contemporary prevention and control strategies.
How do Cats Get Infected With Avian Influenza?
While the current outbreak is still relatively new, it is suspected that feline infections include unpasteurized cow’s milk, raw diets based on meat/poultry products, exposure to infected livestock/poultry and their environments, exposure to wild birds, and exposure to infected cats.
Perhaps most concerning is the documentation of H5N1 infections in exclusively indoor cats. A CDC investigation in Michigan identified two indoor cats that developed severe H5N1 infections despite having no direct contact with birds, livestock, or other infected animals. These cases represent a significant shift in risk assessment, as they demonstrate that even indoor cats may be at risk if household members work in high-risk environments. The cats developed severe neurological disease and died within days of symptom onset, highlighting the continued high pathogenicity of the virus even in these indirect transmission scenarios.
How to Protect Your Cat
Current evidence indicates that no vaccine is available for cats, and treatment options remain limited to supportive care with poor outcomes. I am a big advocate for feeding cats a raw diet, but with the current environment, I have limited Mia's exposure to raw meat. The following recommendations are evidence-based and should be taken seriously.
Elimination of Raw Feeding
The most critical protective measure involves eliminating all raw animal products from cats' diets. Multiple peer-reviewed studies have documented H5N1 transmission to cats through the consumption of raw poultry, unpasteurized dairy products, and contaminated commercial raw pet foods.
The Cornell Feline Health Center explicitly recommends refraining from feeding "raw (even freeze-dried raw) meat-based foods and treats and unpasteurized dairy products."
Consider buying pasteurized freeze-dried instead, like Feastfuls.
While we have eliminated raw feeding for Mia, we continue to feed a meat-based diet for her. We have found a brand that Mia loves and her stomach tolerates fine. While your cat/s may initially resist dietary changes, the transition is essential for protection against avian flu (H5N1) infection.
Indoor Housing Protocols
Maintaining cats indoors represents one of the most effective protection strategies, particularly in regions with documented H5N1 activity in wild birds or livestock.
However, recent cases in exclusively indoor cats have demonstrated that indoor housing alone is insufficient protection if household members work in high-risk environments due to the virus being spread via contaminated clothes as well.
Household members who work with livestock, poultry, or wild birds must implement strict hygiene protocols to prevent bringing H5N1 contamination into the home environment.
Protecting Cats with Outdoor Access
For cats that must be housed outdoors or have outdoor access, owners should implement strict protocols to minimize exposure risks. Cats should be prevented from hunting, scavenging, or otherwise contacting wild birds, which remain the primary reservoir for the H5N1 virus.
For cats that cannot be maintained strictly indoors, owners should implement risk reduction measures, including supervised outdoor time, avoidance of high-risk areas, and immediate return indoors if dead birds or sick wildlife are observed in the area. If you have not done it already, this is a great opportunity to stop your cat from free-roaming. Walking your cat on a harness and leash is the safest way to keep the bird population safe and your cat away from the avian flu.
Understanding if Your Cat Has Bird Flu
Early recognition of H5N1 infection in cats is crucial for implementing appropriate isolation measures and seeking veterinary care, although the rapid progression and high mortality rate of the disease limit treatment options.
Understanding the characteristic pattern of bird flu can help you recognize when emergency veterinary care is needed and when you should implement isolation protocols, particularly if you have more than one cat, to avoid the spread between your cats.
Initial Presentation (Days 1-2)
The earliest signs of H5N1 infection in cats typically appear within 24-48 hours of exposure, reflecting the short incubation period characteristic of this virus.
Initial symptoms are often subtle and may be mistaken for minor illness or stress-related behavior changes.
Behavioral Changes:
- Decreased appetite or complete anorexia
- Lethargy and reduced activity levels
- Hiding behavior or seeking isolation
- Lack of grooming or self-care
- Disorientation or confusion
Physical Signs:
- Elevated body temperature (fever)
- Depression or obtundation
- Protrusion of the third eyelid (nictitating membrane)
- Early conjunctivitis or eye discharge
Rapid Progression (Days 2-4)
Bird flu infection in cats is characterized by rapid clinical deterioration, with symptoms progressing from mild to severe within 24-48 hours. This rapid progression distinguishes bird flu from most other feline respiratory infections and should prompt immediate veterinary attention.
Signs can worsen rapidly to include nasal/ocular discharge, sneezing, coughing, respiratory difficulty, and neurologic signs such as incoordination, tremors, seizures, and blindness.
Respiratory Manifestations:
- Labored breathing (dyspnea)
- Nasal discharge (initially clear, may become purulent)
- Sneezing and coughing
- Open-mouth breathing
- Respiratory distress
Neurological Signs:
- Incoordination (ataxia)
- Abnormal gait or movement
- Tremors or muscle fasciculations
- Seizures
- Blindness or visual impairment
- Abnormal cranial nerve function
Systemical Signs:
- Severe depression or stupor
- Facial swelling or puffiness
- Swelling of lymph nodes
If In Doubt, Rapid Isolation and Veterinary Contact
When bird flu infection is suspected in a cat, immediate action is essential to protect both the affected animal and prevent potential transmission to other cats, animals, and humans.
Rapid Isolation Protocol
The first and most critical step involves immediately isolating the suspected cat from all other animals and minimizing human contact.
- Confine the cat to a separate room with minimal furnishings
- Ensure the room has adequate ventilation
- Remove or minimize soft furnishings that cannot be easily disinfected
- Provide essential supplies (food, water, litter box) within the isolation area
- Restrict access to the isolation area to one designated caretaker when possible
Personal Protective Equipment
All individuals entering the isolation area must wear appropriate personal protective equipment to prevent potential transmission, like disposable gloves, a face mask (N95), and if possible, disposable overalls and eye masks.
Veterinary Contact
The Cornell Feline Health Center specifically advises cat owners to "call your veterinarian immediately," but emphasizes the critical instruction: "do not bring your cat to a veterinarian before contacting them so that they can take appropriate precautions".
Call your veterinarian immediately. But, do not bring your cat to a veterinarian before contacting them so that they can take appropriate precautions.
I really hope you don't find yourself in this situation. If you do, call your vet. They will know what to do next and guide you through the process.
I am not a fan of writing about issues, and I like focusing my blog lightweight and fun, but this issue is here to stay for a while, and like always, better safe than sorry.
Stay wild, stay safe, and I'll see you outdoors!
Albert & Mia
Mary Van Beusekom, MS (2025). Spike in avian flu cases in cats triggers worry about human spillover. CIDRAP. https://www.cidrap.umn.edu/avian-influenza-bird-flu/spike-avian-flu-cases-cats-triggers-worry-about-human-spillover
Cornell Feline Health Center. (2025). H5N1 Avian Influenza and your cat. https://www.vet.cornell.edu/departments-centers-and-institutes/cornell-feline-healthcenter/ health-information/h5n1-avian-influenza-and-your-cat
CDC. (2025). Highly Pathogenic Avian Influenza A(H5N1) Virus Infection of Indoor Domestic Cats Within Dairy Industry Worker Households — Michigan, May 2024. MMWR, 74(5). https://www.cdc.gov/mmwr/volumes/74/wr/mm7405a2.htm
AVMA. (2025). Cat deaths linked to bird flu-contaminated raw pet food, sparking voluntary recall. https://www.avma.org/news/cat-deaths-linked-bird-flu-contaminated-raw-pet-food-sparking-voluntary-recall
2 comments
My 2 beloved cats will be much safer since I’ve read your informative words on bird’s flu. Now I understand the details and reasons/how to take measures. Thank you!
Thank-you for covering this emerging health risk for cats! I think you’ve done an excellent job of drawing together the resources and recommendations cat parents need to help keep their kitties safe and healthy!