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CNN is reporting that the “Centers for Disease Control and Prevention is working with public health officials in 42 states to determine the cause of an outbreak of a particular type of salmonella called Typhimurium.” At least 388 people have been infected and 69 hospitalized since the outbreak in early September.

Reports CNN:

The CDC has not identified what food or foods might be causing this outbreak. It is also not yet releasing a list states involved in the investigation, which they say is ongoing.

CDC officials and state public health workers are conducting case control studies, which means they’re tracking down people who have been infected as early as September to determine what they may have consumed, to find a common cause.

The Food and Drug Administration and the U.S. Department of Agriculture are in contact with the CDC, but without a determination of the cause of the outbreak, their involvement is limited.