The District uses sentinel chickens in rural parts of the county
to detect West Nile virus and other mosquito-borne diseases. They
serve as an early indicator of disease in areas where dead birds
are less likely to be seen and/or reported.
From May through October, sentinel chickens are bled bi-weekly
and their blood is tested for the presence of antibodies
to West Nile virus and
diseases. They are bled humanely by a lancet similar to a
Even if infected with West Nile virus or another mosquito-borne
disease, chickens do not usually get sick, and cannot pass on the
virus to mosquitoes, people, or other birds.
To date, no West Nile virus antibodies have been detected in
sentinel chickens in San Mateo County.
Every summer, the District ‘hires’ 30 chickens to help us monitor
levels of West Nile virus in San Mateo County. Here’s what Vector
Ecologist Tina Sebay had to say about the District’s sentinel