Nov 19, 2012 (CIDRAP News) – Federal and state health officials are investigating an Escherichia coli O157:H7 outbreak linked to mixed salad greens that has sickened at least 28 people in five East Coast states, most of them in New York.
News of sick patients in other states follows a Nov 2 recall of 31,000 pounds of Wegmans Food Markets organic salad mix that was triggered by reports of 16 E coli infections in New York. Authorities, however, said other brands of contaminated leafy greens may be involved in the infections outside of New York.
The US Centers for Disease Control and Prevention (CDC) said today that public health officials have used pulsed-field gel electrophoresis (PFGE) testing to identify other illnesses that may be part of the outbreak. The PFGE pattern associated with the outbreak has been detected only seven times before in PulseNet, the nation's subtyping network, the agency said.
Interviews with 24 of the sick patients revealed that all reported eating prepackaged leafy greens, with 13 of 16 New York patients reporting that they ate the Wegmans greens mix a week before they got sick. Five patients outside of New York who were interviewed reported eating several different brands of prepackaged greens, and investigations are under way to determine if other tainted foods are part of the outbreak.
The CDC said one likely source of the outbreak is State Garden of Chelsea, Mass., which produced the Wegmans greens mix implicated in the outbreak.
Tests on four leftover packages of the leafy greens from sick patients' homes by the New York Department of Health Wadsworth Center Laboratories yielded the outbreak strain, according to the CDC.
Twenty-two of the sick patients are from New York. The other states reporting cases are Connecticut (2), Massachusetts (2), Pennsylvania (1), and Virginia (1). Of 24 patients with information available, 10 were hospitalized, two with hemolytic uremic syndrome (HUS), a potentially fatal kidney complication. No deaths have been reported.
Patient ages range from 4 years to 66 years, and 68% of them are female. Illness-onset dates range from Oct 18 through Nov 3. The CDC and state public health officials are continuing lab surveillance and epidemiologic investigations to identify other cases related to the outbreak.
Nov 17 CDC outbreak announcement
Nov 5 CIDRAP News scan "E coli cases lead to recall of spinach salad mix"