Wildlife Health Alert: Highly Pathogenic Avian Influenza Spreads Across Texas

Highly pathogenic avian influenza is once again making headlines and this time it is widespread across Texas. As migratory waterbirds and waterfowl settle into their wintering grounds, the Texas Parks and Wildlife Department is urging heightened awareness among veterinary professionals, wildlife rehabilitators, and anyone working near birds or susceptible mammals. HPAI has now been detected in all 50 states and Puerto Rico, making this one of the most extensive wildlife disease events in recent memory. While birds remain the primary hosts, the implications reach far beyond avian species and into small animal practice, public health, and wildlife medicine.

Avian Influenza 101 for Busy Clinicians

Avian influenza is caused by influenza type A viruses and exists in many strains that vary in severity. These strains are broadly categorized as low pathogenic avian influenza and highly pathogenic avian influenza. Low pathogenic strains are common in migratory waterfowl and often cause mild or subclinical disease. Highly pathogenic strains are a different story. They spread rapidly, cause severe disease, and carry a high mortality rate in birds. Migratory waterfowl and waterbirds serve as a natural reservoir, allowing the virus to travel long distances and cross species barriers as birds congregate during migration and wintering.

And its not just a bird problem. While poultry producers have long been on alert for HPAI, veterinarians should note that several mammal species are also highly susceptible. These include domestic cats as well as wildlife such as skunks, foxes, raccoons, bobcats, mountain lions, and black bears. In mammals, infection most often occurs through consumption of infected carcasses or exposure to contaminated equipment. This raises important considerations for mixed animal practices, shelters, and wildlife rehabilitation facilities.

Clinical Signs You Should Not Ignore

HPAI does not always announce itself clearly, especially in birds, but when clinical signs are present they can be dramatic.

Common signs include neurological abnormalities such as incoordination, stumbling, tremors, seizures, lethargy, coughing, sneezing, lack of fear of people, and sudden death. Some birds may show no outward signs at all, increasing the risk of silent spread.

Transmission can occur through direct contact with infected birds or indirectly via contaminated equipment, clothing, and footwear. For mammals, ingestion of infected tissue is the primary route.

Texas Parks and Wildlife Department recommends that wildlife rehabilitators exercise caution when intaking animals with signs consistent with HPAI. Quarantine protocols are essential to limit exposure within facilities. Any suspected case of HPAI should be reported to TPWD within 24 hours of intake. Backyard poultry operations are also at risk, as contact with wild birds can lead to infection in either direction. Veterinary clinics that treat outdoor cats or wildlife should review biosecurity protocols and ensure staff understand the risks of fomite transmission.

Current data indicate that the risk of transmission from birds to humans remains low. However, basic protective measures are still recommended when contact with wild animals cannot be avoided. Veterinarians should advise clients and staff to monitor for flu like symptoms following exposure to confirmed or suspected HPAI cases and to contact a health care provider if illness develops. Resources for human health guidance are available through the Texas Department of State Health Services.

Veterinarians play a key role in educating clients and the public. Simple actions can significantly reduce transmission risk. Bird feeders and birdbaths should be cleaned at least every two weeks using a bleach solution of one part household bleach to nine parts water. Water in birdbaths should be changed every few days, and wet or spoiled feed should be removed promptly. Discouraging large congregations of waterfowl near backyard flocks is also critical. Hunters should take precautions including proper carcass disposal, wearing gloves during processing, avoiding sick birds, disinfecting tools between carcasses, and cooking meat to appropriate internal temperatures.

Any wild animal showing signs consistent with HPAI should be reported to a local Texas Parks and Wildlife wildlife biologist.

HPAI is no longer a niche concern limited to poultry farms. It is a statewide and nationwide wildlife health issue with implications for companion animals, wildlife professionals, and public health. Staying informed and proactive helps protect patients, staff, and ecosystems.