Avian Flu Diary: USDA Statement on HPAI In Dairy Cattle in Texas & Kansas Herds

#17,966

This afternoon the USDA announced test findings on the illness in dairy cows I reported on over the weekend (see Curious Reports of Unknown Disease In Dairy Cows (Texas, Kansas & New Mexico) - and just as we saw with goat kids in Minnesota last week - it turns out to be due to HPAI (presumably H5N1).

The USDA's announcement follows, after which I'll have a bit more.

Federal and State Veterinary, Public Health Agencies Share Update on HPAI Detection in Kansas, Texas Dairy Herds
Published: Mar 25, 2024

Wild migratory birds believed to be source of infection; viral testing and epidemiologic efforts continue

Commercial milk supply remains safe due to both federal animal health requirements and pasteurization

Contact: APHISpress@usda.gov

WASHINGTON, March 25, 2024 – The U.S. Department of Agriculture (USDA), Food and Drug Administration (FDA) and Centers for Disease Control and Prevention (CDC), as well as state veterinary and public health officials, are investigating an illness among primarily older dairy cows in Texas, Kansas, and New Mexico that is causing decreased lactation, low appetite, and other symptoms.

As of Monday, March 25, unpasteurized, clinical samples of milk from sick cattle collected from two dairy farms in Kansas and one in Texas, as well as an oropharyngeal swab from another dairy in Texas, have tested positive for highly pathogenic avian influenza (HPAI). Additional testing was initiated on Friday, March 22, and over the weekend because farms have also reported finding deceased wild birds on their properties. Based on findings from Texas, the detections appear to have been introduced by wild birds. Initial testing by the National Veterinary Services Laboratories has not found changes to the virus that would make it more transmissible to humans, which would indicate that the current risk to the public remains low.

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

At this stage, there is no concern about the safety of the commercial milk supply or that this circumstance poses a risk to consumer health. Dairies are required to send only milk from healthy animals into processing for human consumption; milk from impacted animals is being diverted or destroyed so that it does not enter the food supply. In addition, pasteurization has continually proven to inactivate bacteria and viruses, like influenza, in milk. Pasteurization is required for any milk entering interstate commerce.

Federal agencies are also working with state and industry partners to encourage farmers and veterinarians to report cattle illnesses quickly so that we can monitor potential additional cases and minimize the impact to farmers, consumers and other animals. For the dairies whose herds are exhibiting symptoms, on average about ten percent of each affected herd appears to be impacted, with little to no associated mortality reported among the animals. Milk loss resulting from symptomatic cattle to date is too limited to have a major impact on supply and there should be no impact on the price of milk or other dairy products.

This is a rapidly evolving situation, and USDA andCredit U.S. Fish & Wildlife federal and state partners will continue to share additional updates as soon as information becomes available. More information on biosecurity measures can be found here.

Although cattle have previously been successfully infected in the laboratory with older clades of HPAI H5 (see EID Journal Experimental Infection of Cattle with HPAI H5N1), this is the first confirmation of natural HPAI infection in cattle in the United States.

The fact that we're seeing both cattle and goats - across several Midwestern states - suddenly infected with HPAI is a concern, and likely speaks to the amount of virus being carried by migratory birds which are heading north on their spring migration.

Credit U.S. Fish & Wildlife

Since cattle and goats - which have never been infected outside of the lab - are suddenly falling victim to the virus, farms with more far susceptible animals (like swine or mink) may be at a greater risk as well. Some recent warnings include: