Highly Pathogenic Avian Influenza Update

News

January 24, 2025

News article

H5N1 HPAI confirmed in feral domestic cat

Key Points

• A feral domestic cat was picked up in Plaquemines Parish and subsequently neutered.

• The cat was euthanized in Orleans Parish and sent to the Louisiana Animal Disease Diagnostic Laboratory (LADDL) for preliminary testing following signs of neurological disease.

• Presumptive positive results were confirmed by the U.S. Department of Agriculture’s (USDA) National Veterinary Service Laboratory (NVSL) in Ames, Iowa.

• Following monitoring, no signs of avian influenza were detected in the exposed parties.

• No other suspicious cases have been reported.

• If you suspect an animal may be infected with avian influenza, contact your local veterinarian immediately.

• Animal health staff should wear appropriate personal protective equipment (PPE) when in contact with animals suspected or confirmed of being infected with HPAI, acutely sick animals that have a history of exposure to raw milk, wild birds, or raw or undercooked animal products.

Background

On January 24, the Louisiana Department of Agriculture and Forestry announced the detection of H5N1 Highly Pathogenic Avian Influenza (HPAI) in a feral domestic cat in Plaquemines Parish, Louisiana. Some avian influenza viruses can affect animals, such as cats, dogs, and some pocket pets.

Since the current highly pathogenic avian influenza (HPAI) outbreak began, many domestic cats (including pet, barn, and feral cats) have been infected and become severely ill or died from HPAI. Animals can be exposed to the virus and possibly infected from direct contact with infected birds (or their environment) or from consuming contaminated raw meat or raw (unpasteurized) milk.

For information about HPAI detections in mammals throughout the United States, visit the USDA's Detections of HPAI in Mammals webpage .

Clinical Signs

Infection may cause mild to severe disease, including death. Since clinical signs in animals may mimic other respiratory or neurological diseases, HPAI should be considered, especially if known risk factors exist. Risk factors for HPAI infection in animals include:

• Recent exposure to animals or premises known to be infected or contaminated with HPAI

• Recent exposure to or ingestion of dead birds (especially wild waterfowl)

• Recent exposure to or ingestion of raw meat

• Recent exposure to or ingestion of raw cow's milk or colostrum

Clinical signs of HPAI in animals include:

• Fever

• Lethargy

• Inappetence

• Conjunctivitis

• Eye and/or nasal discharge

• Difficulty breathing

• Neurological signs (e.g., tremors, seizures, incoordination, or blindness)

• Death

Prevention

Animals can become infected with avian influenza if they eat infected birds (or other infected animals such as mice), contaminated raw meat (including raw pet food/treats), or contaminated raw milk. Animals may also become infected from direct exposure to contaminated environments or other infected animals, even though the current risk of mammal-to-mammal transmission is considered low in most situations.

We recommend:

• Do not feed animals undercooked or raw meat, including uncooked or freeze-dried meat-based diets, treats, or animal products

• Do not feed animals raw (unpasteurized) milk or colostrum

• Keep animals away from wild birds, poultry, and cattle (especially in areas with known H5N1 outbreaks)

• Prevent animals from eating birds or other wild animals

• Wash hands after handling raw meat and after any encounters with poultry, livestock, or wild animals

• If you interact with any sick or dead animals that may harbor avian influenza virus, change your clothes and shoes and wash your hands thoroughly

• If you suspect your animal may be infected with avian influenza, contact your veterinarian immediately

While HPAI is typically a respiratory virus in its natural hosts, ingestion is an important route of infection in most species, especially mammals. Mammal infections typically result in acute to per-acute neurological symptoms and encephalitis, although the symptoms are dose-dependent and in some mammal cases with minimal exposures, symptoms may be mild to moderate, and patients may recover.

HPAI should be considered as a rule-out in encephalitis or other cases exhibiting neurological symptoms or acute respiratory distress without a clear disease process diagnosed. A history of exposure to sick poultry, wild waterfowl, or consumption of raw milk, raw meat, or raw animal food are important risk factors for consideration.

Because of the zoonotic potential, additional precautions also should be taken to protect clinic staff with any patient where HPAI is suspected. At a minimum, the CDC high-risk personal protective equipment (PPE) guidance should be followed whenever handling a patient with suspected HPAI.

Resources

Louisiana Department of Health – Office of Public Health – Avian Influenza

American Veterinary Medical Association – Avian Influenza in pets and backyard flocks

US Department of Agriculture (USDA) – Highly Pathogenic Avian Influenza (HPAI) Detections in Mammals

US Centers for Disease Control and Prevention (CDC) – Considerations for Veterinarians: Evaluating and Handling of Cats Potentially Exposed to Highly Pathogenic Avian Influenza A (H5N1) Virus

US Centers for Disease Control and Prevention (CDC) – Influenza in Animals

US Centers for Disease Control and Prevention (CDC) – H5 Bird Flu: Current Situation