Infections have occurred in eight states, including California, Tennessee, and New Hampshire, with eight people requiring hospitalization. No deaths are currently reported.
The agency cites interviews with sick people and laboratory testing that show contact with wild songbirds and bird feeders could be driving the infections.
The California Department of Fish and Wildlife reports being “inundated” with calls about residents finding sick or dead finches at or around bird feeders, particularly around the state’s central coast and in the San Francisco Bay Area.
One species in particular, pine siskins, is most frequently the subject of those calls in the state.
Birds can contract salmonella when they eat birdseed that is contaminated with the feces from other birds, often on the ground below bird feeders.
Birds often carry bacteria such as salmonella, and the germ can spread from birds to pets, and to people, the agency says.
In humans, salmonella illness can involve diarrhea, fever, and stomach cramps, tends to last four to seven days and most people can recover without treatment, the CDC says. Some severe cases, however, do require hospitalization.
The CDC recommends that people wash their hands immediately after they touch a bird feeder, bird bath, or handle a bird, even if they were wearing gloves. It also advises cleaning bird feeders outside your house, when possible.