The CDC now recommends routine testing for dairy workers exposed to H5N1 bird flu in the U.S., even if they show no symptoms. Blood tests from workers in Colorado and Michigan revealed some asymptomatic cases. The CDC urges using Tamiflu for exposed workers, and officials highlight no evidence of person-to-person transmission. States with significant cases include California, Washington, and Colorado, with symptoms generally mild.
The U.S. Centers for Disease Control and Prevention (CDC) has advised that dairy workers who may have been exposed to the bird flu virus H5N1 should undergo testing and receive antiviral treatment, regardless of symptoms. The CDC’s new recommendation aims to prevent silent infections and reduce potential transmission risk from animals to humans.
Recent studies in Colorado and Michigan revealed asymptomatic H5N1 infections among some dairy workers. Blood tests on 115 farmworkers showed that eight had antibodies for the virus, indicating prior infection. Despite this, there is no evidence of person-to-person transmission, CDC Deputy Director Dr. Nirav Shah emphasized.
H5N1 cases, primarily linked to exposure to sick animals, have surfaced in the United States, with 46 confirmed infections so far this year, including 21 in California, 11 in Washington, and 10 in Colorado. Infections have led to mild symptoms such as red eyes and minor respiratory discomfort, with no fatalities reported. This outcome contrasts with past global H5N1 outbreaks, where mortality rates were higher, possibly due to variations in virus genotypes.
Jennifer Nuzzo, director of Brown University’s Pandemic Center, criticized the delayed response in testing asymptomatic workers, citing missed opportunities to detect potential cases early. The CDC now advises testing any farmworker significantly exposed to bird flu, particularly those handling raw milk from infected herds.
Farmers and workers will not bear the cost of these additional tests, according to a CDC spokesperson, though funding sources for broader testing remain unclear.
