Health officials are investigating a nationwide outbreak of the parasite Cyclospora. A source familiar with the probe says some individuals sickened reported eating at Taco Bell, while others did not, suggesting multiple potential sources.
Identifying the source is difficult due to a two-week symptom delay and complex food distribution networks. The CDC is tracking the outbreak across at least 31 states, with over 4,000 cases reported this summer.
Michigan is seeing the highest number of illnesses. New York has reported 470 cases, Ohio at least 397, and North Carolina over 240.
Health officials are recommending caution with leafy greens, particularly bagged or boxed salads. They advise buying whole heads of lettuce, discarding the outer leaves, and washing thoroughly. Cooking produce to 158°F (70°C) is the safest method to kill the parasite.
Past outbreaks have been linked to bagged salad mixes, cilantro, basil, raspberries, and snow peas. Symptoms include frequent watery diarrhea. People should consult a healthcare provider, as antimicrobial treatments are available.