An outbreak of explosive diarrhea caused by the parasite *Cyclospora cayetanensis* is already affecting 34 U.S. states and could reach Mexico in the coming weeks, infectious disease specialist Alejandro Macías warned on Wednesday; he noted that he has already treated cases of the parasite within the country.
The Centers for Disease Control and Prevention (CDC) have reported 1,645 confirmed cases since May—a figure four times higher than that of the same period in 2025—and the investigation into the source of contamination remains ongoing.
The parasite is not transmitted from person to person. It requires about a week to mature in the environment before becoming infectious, and it primarily contaminates the irrigation water used for leafy green vegetable crops. Macías warns that the temperature and humidity conditions during Mexico’s rainy season are conducive to its spread.
“The conditions are right, especially regarding temperature and humidity during the rainy season. It is entirely possible for it to arrive,” Macías said in an interview with Uno TV.
