The USDA has worked to entice dairy farmers to allow bird flu testing; anonymous testing is the latest pitch

Dairy farming is expensive and labor intensive. Cows have to be
milked twice a day. (Wisconsin Dairy photo)

Department of Agriculture scientists want to sample U.S. dairy herds for bird flu infections, but many dairy farmers won't allow testing. As a workaround, the USDA is suggesting anonymized testing, reports Tina Reed of Axios. "Many farmers are refusing to test their herds, fearing the economic consequences, while concern builds that the relatively benign virus could morph into a much bigger risk to humans."

Ashish Jha, who is dean of Brown University's School of Public Health, is among a small group of public health officials who would like universities to work with dairy farmers to facilitate herd testing. Reed explains, "Results from individual farms would be anonymized and sent to the USDA to offer snapshots about disease spread and how the virus is mutating, Jha said. . . . The idea has limitations, starting with the difficulty of zeroing in and addressing transmission at the source, experts said."

To date, the USDA has documented 140 U.S. herds across 12 states that have been affected by bird flu, or H5N1. "But prevalence is thought to be higher because many farmers are refusing to test," Reed reports. "Positive tests could be 'financially ruinous' for farms and individual workers, while the consequences of not testing so far appear to be limited to mild illness that can be treated with antivirals, Jha said." Jha told Axios: "It's not really clear for [dairy farmers] why they should engage."

But testing herds isn't the only method to assess bird flu's prevalence in dairy cows. Reed writes, "Another way of getting a better picture of bird flu activity in an anonymized way would be through the use of what's known as market basket surveys, Michael Osterholm, director of the Center for Infectious Disease Research and Policy at the University of Minnesota told Axios. . . The surveys, which have been used in Europe and Canada during this outbreak, are routine scans of pasteurized milk samples for traces of inactivated virus."

Osterholm told Reed, "The movement of milk is very, very closely monitored. While a sample couldn't necessarily be traced back to a specific farm, it could get close. It could give us a sense if there are certain areas of activity."