Since an unusual bird flu outbreak was first detected in dairy cows in March, experts have warned that the virus could be infecting more farm workers than have been officially detected.
In recent weeks, state and federal officials have been working to unravel part of that mystery: whether silent, undetected infections are occurring in farm workers.
Officials in Michigan recently began testing the blood of 35 dairy workers for antibodies to the virus, which would provide evidence of past infection.
All worked on dairy farms in Michigan that had suffered outbreaks, and many worked directly with sick cows, the agency said.
The farm workers tested were also volunteers, which means that they may not be representative of dairy workers more broadly.
Persons:
Natasha Bagdasarian
Organizations:
Centers for Disease Control
Locations:
Michigan