This move by the USDA to heighten testing requirements for HPAI H5N1 follows the disclosure by the Food and Drug Administration on Tuesday that samples of pasteurized milk sold in grocery stores had tested positive for the virus.
This discovery prompted further investigation to ascertain whether the positive test results were due to lingering dead “virus particles” or live infectious virus.
Moreover, federal authorities have noted “isolated” yet concerning alterations to the virus in cows, which U.S. officials believe may have contracted the virus from wild birds.
State veterinarians and laboratories identifying cattle that have tested positive for the virus will be mandated to report their findings to the USDA. Farms with afflicted cows will be subjected to investigations before they can transport cattle across state lines.
According to officials, the virus was not initially detected in the respiratory tract of most infected cows, indicating that it is not spreading through the air between cows like other strains of influenza. Instead, H5N1 HPAI in the current outbreak has predominantly been detected in raw milk and the cow organs responsible for its production.
Officials speculate that the virus may have disseminated among cows during the milking process on farms or through surfaces contaminated with infected raw milk.
