Navigating HPAI: Dairy Market Resource Center

Key News This Week:

April 24: FDA Finds Traces of H5N1 Bird Flu Viruses in Grocery Store Milk but Says Pasteurized Dairy Products are Still Safe

April 24: U.S. FDA Updates on Highly Pathogenic Avian Influenza (HPAI)

Breaking News: USDA APHIS Limiting Cattle Movement; HPAI Found in Milk Samples, Likely Inactive – 24 April, 2024

USDA’s Animal and Plant Health Inspection Service (APHIS) has issued a Federal Order related to limiting the movement of cattle effective April 29, 2024. The agency has found that the same HPAI H5N1 virus genotype that has impacted dairy cows is also affecting poultry flocks. The agency has shared that the disease can spread cattle-to-cattle, as evidenced by transmission via movement between herds. APHIS also shares that, “…we have similar evidence that the virus also spread from dairy cattle premises back into nearby poultry premises through an unknown route.”

Given the virus is deadly for birds, this measure seeks to prevent the spread of the virus and limit losses to poultry farmers. Further, there is overlap in the dairy herd and poultry flocks in Kansas, Michigan, New Mexico, and Texas as the disease has popped up in both species. Notably, Texas and Michigan rank in the top ten in the US for chicken production. Further, while poultry flocks in North Carolina have not been affected, dairy cows have, and North Carolina is one of the top states in the US for chicken and turkey production. Minnesota and Pennsylvania are also worth mentioning, as well, as both states are ranked in the top 10 for dairy, chickens, and turkeys; the disease has shown up in birds in Minnesota.

APHIS is requiring the following for interstate movement of cattle:

Prior to interstate movement, dairy cattle are required to receive a negative test for Influenza A virus at an approved National Animal Health Laboratory Network (NAHLN) laboratory.
Owners of herds in which dairy cattle test positive for interstate movement will be required to provide epidemiological information, including animal movement tracing.
Dairy cattle moving interstate must adhere to conditions specified by APHIS.
As will be described in forthcoming guidance, these steps will be immediately required for lactating dairy cattle, while these requirements for other classes of dairy cattle will be based on scientific factors concerning the virus and its evolving risk profile.

Moving forward, mandatory reporting will be required of state veterinarians and laboratories. Any positive Influenza A tests via nucleic acid detection or serology diagnostic results must be reported to USDA APHIS.

In addition to this news, The US Food and Drug Administration has reported that Highly Pathogenic Avian Influenza H5N1 has been detected in raw milk and in samples or pasteurized milk via qPCR, or quantitative polymerase chain reaction testing. The number of samples or sources was not shared. Per the FDA, “Quantitative polymerase chain reaction (qPCR) is a screening tool used to determine the presence or absence of an organism’s genetic material in a sample. A positive qPCR means that the genetic material from the targeted pathogen was detected in the sample, but that does not mean that the sample contains an intact, infectious pathogen.” In other words, although a virus’ DNA may be found in pasteurized milk, a positive test does NOT imply that the virus is live and infectious with the ability to spread to humans.

The FDA is actively conducting further tests to ascertain if HPAI remains infectious in pasteurized milk, as qPCR does not offer that level of detail. The methodology being employed is embryonated egg viability studies, regarded as the “gold standard” for detecting active viruses. While this method may take longer than other tests, it provides a distinction between live and inactive viruses. The FDA anticipates that more information from these follow-up tests will be available in the coming days to weeks, ensuring the public is kept up to date on the situation.

The FDA remains firm that the commercial milk supply is safe, citing pasteurization and diversion of milk as two key safety measures. The FDA, CDC, and USDA APHIS continue to remind consumers not to drink raw milk (unpasteurized) as it carries the danger of contracting a variety of diseases, noting that pasteurized milk does not carry those risks. Additionally, the FDA cites several studies that found pasteurization to be an effective way to deactivate heat-sensitive viruses, like HPAI H5N1, in eggs and milk. Further, farmers are required to dispose of or divert milk from sick cows, as part of the Pasteurized Milk Ordinance, so that it does not enter the food chain, providing another measure to keep the milk supply safe.

Respected infectious disease experts, including Dr. David O’Connor, Dr. Nahid Bhadelia, and Dr. Michael Osterholm, have echoed the FDA’s position, stating that it is not unusual to find viral fragments in milk and that there is likely no risk to consumers. Dr. Osterholm, in an interview with NBC News, stated, “From an influenza standpoint, I wouldn’t hesitate to drink milk tonight. Even my grandchildren could safely consume the milk tonight.” This endorsement from renowned experts further underscores the safety of pasteurized milk.

That said, various major news outlets are reporting this story, and it is possible that consumers may get nervous by the headlines despite the assurances that milk is safe. Customer perception can influence milk markets, and a downturn in buying would likely push prices lower in the near term.

HighGround will continue to provide updates as more information becomes available.

On March 25, USDA’s Animal and Plant Health Inspection Service (APHIS) confirmed that sick dairy cattle in Texas and Kansas tested positive for Highly Pathogenic Avian Influenza (HPAI), specifically Type A(H5N1). Friday, March 29, cases were confirmed in Michigan, thought to have come from animals transported from Texas. The agency shared that cattle-to-cattle transmission could not be ruled out. Presumptive positive tests were pending from dairies in New Mexico and Idaho. Bird flu tends to spread from wild waterfowl, and that is the cause USDA is positing presently. And on April 1, the Central for Disease Control shared that a worker on a Texas dairy tested positive for HPAI A(H5N1), perhaps suggesting that the disease could spread to humans.

USDA has reiterated that milk and meat from impacted animals is safe. Pasteurization kills viruses and microbes. Further, per the Pasteurization Milk Ordinance, milk from any sick cows (HPAI or not) is to be diverted from the human supply chain. Consuming raw milk or dairy products made with raw milk is not recommended by the Food and Drug Administration, due to increased risk for diseases such as listeria. The organization has shared that it is unclear if HPAI can be spread via raw milk, reiterating that unpasteurized milk can pose “serious health risks to consumers.” Trade organizations have emphasized biosecurity practices, including quarantining sick cows and limiting cattle movement. To date, no formal efforts or policies have been put forth by USDA to limit interstate cattle transportation.

While infected cows have dropped in milk production, some bounce back after HPAI. However, some do not, and they are culled. That said, the longer-term impact on supply is not entirely clear, as farmers are trying to maintain herd inventories in a time of tight cattle supplies. Additionally, more information and knowledge about the disease is becoming available. Presently, the length of time a cow needs to come back to normal production after being ill, and if it is economical, is not fully understood.

Demand could be a concern for a couple of reasons. First, consumer perception of HPAI in dairy cattle may not be positive, and that could cause a decrease in dairy consumption. Further, only the US is reporting HPAI in dairy cattle, and other countries could limit imports of dairy, similar to what occurred during the H1N1 outbreak in 2009.

For all the important headlines and resources, please see below: