Highly Pathogenic Avian Influenza Identified in Goats and Cattle

By Katie Drewitz

HPAI historically infects birds but has been documented to infect mammals such as cats, skunks, and foxes. Based on the recent findings from Michigan USDA announced the virus is very similar to the viruses found in Texas and Kansas and reiterated the virus appears to have been introduced by wild birds.

Pasteurization has continually proven to inactivate bacteria and viruses, like influenza, in milk. FDA’s longstanding position is that unpasteurized, raw milk can harbor dangerous microorganisms that can pose serious health risks to consumers. FDA is reminding consumers of the risks associated with raw milk consumption in light of the HPAI detections.

USDA stated that initial testing has not found changes to the virus that would make it more transmissible to humans and that while cases among humans in direct contact with infected animals are possible, this indicates that the current risk to the public remains low.

If you are working directly with cattle that have tested positive or fit the case profile and you are experiencing flu-like symptoms, please consult your physician. Human cases of influenza must be confirmed with testing, they cannot be diagnosed based on symptoms alone.

USDA and Federal agencies are moving quickly to conduct additional testing for HPAI, as well as additional viral genome sequencing, so that we can better understand the situation, including characterization of the HPAI strain or strains associated with these detections.

 Veterinarians working with potentially impacted farms should consult with state health officials and their diagnostic laboratories to ensure they follow established diagnostic sampling guidelines.

At this time, impacted herds do not appear to be experiencing mortalities associated with this disease syndrome. In impacted herds, approximately 10% of cattle are affected, with the majority of cases being mid to late-lactation mature cows. Impacted herds are experiencing approximately 10-20% reduction in milk production for a 14- to 21-day period. At this time, dry cows, fresh cows, heifers, and calves do not appear to be affected.

Affected cattle:

• Have symptoms that last between 10 and 14 days with the worst of the symptoms peaking in the first 3-5 days.
• Have a sudden drop in milk production, with severe cases producing thicker, more concentrated milk that appears colostrum-like.
• Have a drop in feed intake and rumination activity.
• Mostly have tacky, dehydrated feces, but a small number have loose feces.
• Can experience secondary infections including pneumonia and mastitis.

If you feel your herd’s symptoms are consistent with the reported illness consult with your herd veterinarian or the MN Board of Animal Health (https://www.bah.state.mn.us/) immediately.

Based on these cases, cattle (dairy and beef) owners are encouraged to follow recommended biosecurity practices for mitigating 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 species and minimize poultry access to pasture areas that are grazed by other livestock species.
• Minimize or eliminate (when possible) poultry, waterfowl, and wildlife access to potentially shared water sources and feedstuffs (e.g., cover and secure feed piles).

At this time, it is unclear if the illness can be spread from cow to cow or by inanimate objects such as vehicles or equipment. Cattle (dairy and beef) owners are encouraged to follow these biosecurity practices for livestock:

• Limit visitors to your farm, and consider having meetings away from the farm when possible.
• Minimize the interaction of on-farm vehicle routes and off-farm vehicle routes.
• Ensure equipment used to transport animals (i.e. trailers) is clean and washed between uses, this includes your trailers in addition to outside-hired transport. Inspect these trailers before use to ensure they have been cleaned.
• Cattle transported to a new premise should be quarantined and isolated for 21 days to monitor for clinical signs before joining the herd.
• Deceased animals should be disposed of promptly and appropriately; this can include composting, deep burial to prevent wildlife interaction with the carcass, or rendering. Minimize the interaction of the rendering truck with on-farm vehicle routes and animals.
• When possible, personnel should have dedicated clothing, boots, and other PPE for the farm that stays on the farm.
• Service providers are encouraged to have dedicated equipment as well as clothing, boots, and other PPE for farms they visit regularly. Boot washing and disinfection, equipment washing and disinfection, and changing soiled clothing are recommended when dedicated equipment is not possible.
• FDA is recommending milk intended for consumption by animals, including calves, from cows that are infected or have potential contact with infected animals, should be pasteurized.

Based on this case, owners of small ruminants, horses, and other livestock are reminded to follow recommended biosecurity practices, including:

• Do not allow poultry and livestock species access to ponds, wetlands, and other stagnant water sources that are frequented by wild waterfowl (e.g., ducks, geese, swans).
• Watch poultry and livestock for signs of illness, including reduced appetite, fever, inability to stand, depression, nasal discharge, diarrhea, coughing, and change in behavior.
• Consider housing poultry separately from other livestock species and minimize poultry access to pasture areas that are grazed by other livestock species.
• Do not allow poultry, waterfowl, and wildlife to share water sources and feedstuffs with other livestock species.
• Unfortunately, current influenza vaccines used in horses are not effective against HPAI; always consult your veterinarian before administering vaccinations.
• 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 provide protection against influenza.
• If you have an unexplained death in one of your animals, consult with your farm veterinarian or contact the MN BAH.

If you have questions about this or any other agriculture or horticulture topic, please reach out to your local Extension Educator. Fillmore and Houston County residents can (507) 765-3896 or (507) 725-5807. 

Katie Drewitz is the University   of Minnesota Extension Agriculture, Production, Horticulture & Natural Resources educator for Fillmore and Houston Counties.