Three of America’s leading milk-producing states don’t participate in federal surveillance testing of bird flu, even though a new variant has been found in dairy cows. This is what some public health specialists say is an alarming gap in the nation’s effort to detect and identify the virus.
In December, the U.S. Agriculture Department began a voluntary program of milk testing after it was discovered that the virus had spread to cattle in March. The outbreak of avian flu in the United States began in 2022 but has gained momentum over the past year. It has decimated poultry farms across the country, killed tens of millions of birds, and driven up the price of eggs.
Many public and animal health professionals argue that nationwide testing is crucial to contain virus cases that might otherwise go unnoticed, giving the variants a greater opportunity to spread to both animals and humans.
The American Association of Bovine Practitioners, which represents cow vets, said that it is “incredibly difficult” to control a national disease without a robust surveillance program.
If we tested every dairy, there wouldn’t be any cases that slip through.
Texas, Wisconsin, and Idaho are three of the top five states in terms of milk production, but they don’t participate in the voluntary federal program. Although efforts are being made to bring them on board, there is no indication of when or how long this will take.
Texas has had the first case of bird influenza in cattle and the first mammal to be believed to have infected a person. A case was also found in dairy cows in December. Sid Miller said that surveillance milk testing is not necessary because there are no active bird flu cases in commercial cattle and poultry.
Miller told an interview that it was not a major issue if measured by the number of herds affected.
Testing milk for bird flu is “just more regulation and cost.” He said that it was not necessary, but the state still regarded bird flu as a serious threat.
According to the USDA, a separate agency, the Animal Health Commission of the state, works with federal officials on a surveillance program for bird influenza.
The USDA just announced last week that it discovered a strain of TB in cattle caught in Nevada by the federal milk testing program.
In a press release, the USDA stated that the detection was “a testament to our National Milk Testing Strategy”. Last month, the USDA announced that samples were being collected from almost three-quarters of all milk produced in the United States. Since then, nearly 40 states have now been involved. The USDA aims to enroll all 48 states in the continental United States.
According to the U.S. Centers for Disease Control and Prevention, one person died and 68 others were infected since the start of 2024. This was most commonly after prolonged or close contact with animals infected.
Richard Webby is an animal flu expert at St. Jude Children’s Research Hospital. He said that the milk test is a crucial tool to help disease specialists monitor the virus’s evolution, particularly in ways that could make it more easily transmitted from one person to another.
He said: “We can determine if changes are occurring within the virus which increase human risks.”
Pasteurization kills the bird flu found in milk. It is safe to drink. However, farmworkers still come into contact with raw cow’s milk and milk that may be infected. So far, more than 960 herds of dairy cows have been infected. The federal government has mandated that all lactating milking cattle be tested before they are moved between states.
State and USDA officials test raw milk samples collected from bulk silos. This is where farm milk is collected and sent to processors who pasteurize, homogenize, and package it. The USDA maintains a network of national labs that test for bird flu. Federal requirements require a minimum of four rounds of testing over six months. Follow-up tests are also required to track down any positive results for specific farms. The agency offers free testing for individual farmers.
Wisconsin is “continuing to work towards” enrolling in USDA’s bird flu testing program. The state is also working closely with federal and state partners to monitor the development of the virus, according to the spokesperson for the state agricultural department.
USDA reports that Idaho has not responded to any requests for comment, but does not participate in the program at this time.
Health experts say that bird flu can be detected by testing even before symptoms in dairy cows are evident. This can help farmers quickly quarantine animals affected and test people who may have been exposed.
The more time we have to identify where the virus is, the better protection workers can receive. Dr. Kay Russo said. She was a Colorado vet who helped confirm the first case of bird influenza in cattle in the past year.
Russo continued, “If we are flying blindly in a certain state, and we don’t have a clear picture of the situation, we can’t be sure what the risks are.”
Even within states that are enrolled in USDA’s program, the frequency of testing milk varies greatly across the United States.
Colorado, where testing is done monthly in some states, required that all farms test milk weekly after an outbreak of disease in dairy cows last year.
“It helps our poultry and milk industries sleep at night,” Dr. Maggie Baldwin said. The state’s testing program helped detect cases even before animals showed symptoms. “We know exactly where the disease is.”
