Epidemiologic and traceback investigations conducted in Texas from three restaurants and one grocery store indicated that some of the 278 illnesses in the state were linked to fresh cilantro from Puebla, Mexico.
Texas reported the highest case count, with Iowa (153) and Nebraska (86) also being hit hard.
643 people were sickened in total from 25 states from mid-June to mid-July.
During interviews with ill people in Texas, about 50% reported having eaten fresh cilantro 2–14 days before they became ill, significantly higher than that of ill people in Iowa and Nebraska (reported by about 10%).
Thirty ill people reported eating at a single Mexican-style restaurant in Fort Bend County, Texas, in the 2–14 days before onset of illness.
An analytic epidemiologic study compared foods eaten at the restaurant by 25 of the sickened people versus 65 healthy people.
Four fresh produce ingredients were significantly associated with illness: cilantro, whole onions, garlic, and tomatoes, said the CDC.
Fresh cilantro was the only ingredient consumed by all 25 ill people in the study and salsa containing fresh raw (uncooked) cilantro was associated with illness, while salsa containing cooked cilantro was not.
The three salsas that were not cooked were significantly associated with illness and the one that was cooked before serving was not (heat can kill Cyclospora).
Two separate outbreaks
It was reported that the illnesses in Texas did not show a connection to others in August.
Data suggests that there was more than one outbreak of cyclosporiasis during June–August 2013 in the US, said the CDC.
There is no evidence to suggest that contaminated salad mix from Taylor Farms de Mexico or fresh cilantro from Puebla, Mexico, is still on the market, the agency added.
Public health officials in Iowa and Nebraska performed investigations within their states and concluded that restaurant-associated cases of cyclosporiasis were linked to a salad mix produced by Taylor Farms de Mexico.
Taylor Farms voluntarily suspended production and shipment from its operations in Mexico to the US after the incident.
However, the firm resumed production and shipment of salad mix, leafy greens, and salad mix components from Mexico to the US after Food and Drug Administration (FDA) approval in August.
Among 581 ill people with available information, 45 (8%) have reported being hospitalized while no deaths have been reported.