Local health officials in Hopkins County, Ky., have confirmed an outbreak of Salmonella, according to news reports. Health officials confirmed 10 cases and one fatality. The outbreak source is unknown.

Investigators with the Hopkins County Health Department will be interviewing victims to determine what they might have eaten before falling ill. Barry Franklin, environmental supervisor for the health department, told WKMS that he first heard about a possible outbreak on Sept. 18. He added that it’s the worst outbreak he’s seen in 19 years on the job.

Symptoms of Salmonella infection include diarrhea, fever, headache and abdominal cramps. Symptoms usually appear 12 hours to four days after exposure, and a person can be sick for four days to a week.