Breaking down what a false positive does (and doesn’t mean) in the Cyclospora investigation, plus updates on measles, Ebola, and Legionnaires’ disease.

Shredded iceberg lettuce from Mexico, supplied by Taylor Farms to Taco Bell (and possibly other vendors), is the likely culprit in the outbreak in MI, OH, IN, KY, and WV. Meanwhile, terrible air quality from wildfires is affecting the Midwest and Northeast.