Cattle from Texas and Kansas have tested positive for Highly Pathogenic Avian Influenza (HPAI).
HPAI historically infects birds but has been documented to infect mammals. Based on the findings from Texas, the virus appears to have been introduced by wild birds. Federal and state agencies are moving quickly to conduct additional testing for HPAI, as well as viral genome sequencing, so that they can better understand the situation, including characterization of the HPAI strain or strains associated with these detections.
At this time, information from USDA, FDA, and CDC indicates the risk to the public is considered low and there is no concern about the safety of the commercial milk supply and no concern that this issue poses a risk to consumer health. Pasteurization has continually proven to inactivate bacteria and viruses, like influenza, in milk.
People should avoid consuming raw milk or raw milk products. Dairies are required to send only milk from healthy animals for human consumption. Milk from impacted animals does not enter the food supply.
Additional locations with similar case profiles have been identified and are waiting for test results. Farmers and veterinarians are encouraged to report cattle illnesses quickly so that USDA APHIS can monitor potential additional cases and minimize the impact to farmers, consumers and animals.
Veterinarians working with potentially impacted farms should consult with state health officials and their diagnostic laboratories to ensure they follow established diagnostic sampling guidelines.
Animals do not appear to be dying from this disease in impacted herds. In impacted herds, approximately 10% of cattle are affected, with most cases affecting mid to late-lactation mature cows. Impacted herds are experiencing approximately 10 to 20% reduction in milk production for 14 to 21 days. At this time, dry cows, fresh cows, heifers and calves do not appear to be affected.
Symptoms in affected cattle
- Symptoms last between 10 and 14 days with the worst of the symptoms peaking in the first 3 to 5 days.
- A sudden drop in milk production, with severe cases producing thicker, more concentrated milk that appears colostrum-like.
- A drop in feed intake and rumination activity.
- Most have tacky, dehydrated feces; a small number have loose feces.
- Can experience secondary infections including pneumonia and mastitis.
Biosecurity measures needed
Based on these cases, cattle (dairy and beef) owners are encouraged to follow recommended biosecurity practices to reduce or eliminate livestock and avian interaction including:
- Minimize or eliminate (when possible) poultry and livestock species access to ponds, wetlands, and other stagnant water sources frequented by wild waterfowl (ducks, geese, swans).
- Monitor cattle for signs of illness, this includes decreased milk production, decreased feed intake, fever, dry or tacky feces and depression.
- Monitor domestic poultry for illness, this includes reduced appetite, reduced water intake and unexplained deaths.
- Monitor cats, wild waterfowl and wildlife that are frequently found around livestock facilities for illness or unexplained deaths.
- Consider housing poultry separately from other livestock and minimize poultry access to pasture areas that are grazed by other livestock.
- Minimize or eliminate (when possible) poultry, waterfowl and wildlife access to potentially shared water sources and feedstuffs (cover and secure feed piles).
- Many cattle are vaccinated against Parainfluenza-3 (PI-3), a virus that can cause respiratory issues. Parainfluenza viruses are in a different family from influenza viruses and the PI-3 vaccine does not protect against influenza.
- If you feel your herd’s symptoms are consistent with an Influenza A infection, consult your herd veterinarian or the Minnesota Board of Animal Health immediately.
We will share additional information as we learn more. For updates, please continue to check this website, the USDA APHIS website, and the Minnesota Board of Animal Health website. You can also listen to The Moos Room podcast for updates.
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