The Center for Disease Control (CDC) is investigating a multi-state outbreak of Salmonella Typhimurium infections.
CDC lab data show that contact with wild songbirds and birdfeeders is likely causing people to get sick.
As of March 30, 19 people have been infected in eight states. The first reported illnesses began in December.
The CDC says that wild songbirds, such as pine siskins, can be found throughout the U.S so the outbreak of salmonella may not be limited to the states reporting illnesses.
Out of the 13 people the CDC interviewed, 9 of them (nearly 70%) reported owning a bird feeder and two others said they had made contact with a sick or dead bird.
The CDC recommends that people not touch or hand-feed wild birds with bare hands and always wash hands after touching wild birds, bird feeders and bird baths.