Highly pathogenic avian influenza (HPAI) is a type of avian influenza virus that was first detected in dairy cattle in March 2024. Otherwise known as bovine influenza A, HPAI in dairy is caused by the H5N1 virus strain that has spread from birds to infect other species. It is thought to have spread from poultry to dairy in one spillover event that occurred in December 2023. Since then, it has spread from dairy to dairy and from dairy to other species. As of June 2024, it has affected dairies in 12 states across the United States.
Veterinarians and industry experts have emphasized how a positive case of HPAI on a farm could have a significant impact on your herd health, milk production, and economic viability. According to Michigan State University, it could take 30 days for the virus to move through the herd, with farms reporting a 15% to 20% loss in milk production at the virus’ peak. While it is too soon to tell the long-term effects on dairy herds, reproduction and longevity could potentially be affected.
Over the past couple months, the Center for Dairy Excellence has worked closely with the Pennsylvania Department of Agriculture and other organizations to host industry calls and share updates about the situation. To protect your dairy from disease threats like HPAI, here are five tips we have learned from experts who have joined our calls.
1. Keep a close eye on animal movement. Follow guidelines regarding pretesting and keep new cattle isolated for at least 21 days. Among the dairies whose herds are exhibiting symptoms, the affected animals have recovered after isolation with little to no associated mortality reported. Do not share trailers between herds, and sanitize equipment in between moving.
2. Step up your biosecurity. Biosecurity planning resources for Pennsylvania dairy producers are available from the PA Department of Agriculture, Penn State Extension, and the Center for Dairy Excellence. Other dairy organizations across the country, such as the National Milk Producers’ Federation (NMPF), are providing additional biosecurity resources to producers.
3. Know who is coming onto your operation. Limit visitors who are nonessential and require essential visitors to practice cleaning and sanitation when they arrive and when they leave. Be sure to outline your expectations for visitors and have those expectations posted to ensure everyone is following your biosecurity protocols.
4. Be prepared. Prepare your biosecurity plans, identify what disinfectants you need to have for cleaning and sanitation, and have protection for your employees just in case. Bovine influenza A is primarily spread by birds to dairy cattle, so limiting wild bird exposure can help. It will also spread on farms by people carrying matter from infected birds — such as dust, dander, and bird droppings — on their clothing, gloves, soles of their shoes, vehicle tires, animal trailers, and other equipment, in addition to contaminated water. Keeping equipment, clothing, and footwear clean helps protect cattle from many viruses and bacteria.
5. Talk to your personnel and work closely with your veterinarian. Do the education on your farm to make sure your employees know what symptoms to look for to detect the virus. Keeping sick animals or animals that are showing signs of infection away from the rest of the herd is important. If you observe clinical signs in your herd consistent with this outbreak, contact your veterinarian immediately.
