As of mid-august, the U.S. Centers for Disease Control and Prevention (CDC) reported over 15,000 Cyclospora parasite infections since may, leading to more than 800 hospitalizations and two deaths.
The outbreak originated from contaminated pre-cut lettuce produced by Taylor Farms de Mexico, which was distributed to numerous supermarkets and restaurant chains across the United States. The Cyclospora parasite spreads through contaminated food, water, and human feces, causing severe diarrhea, nausea, and fatigue.
The CDC suggests that the actual number of infections could be higher, as many patients experience only mild symptoms. Officials in Michigan reported 14,000 suspected or related cases since june.
"When you see 10,000 reported cases, the actual number of infections could be 10 to 20 times higher," stated Scott Gottlieb, former director of the U.S. Food and Drug Administration (FDA). He noted that this is the largest Cyclospora outbreak in history.
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Consumers buying lettuce at a supermarket in the United States. Photo: *USA Today*.
Despite the FDA's assertion that all affected lettuce has been recalled, a CBS News survey revealed that 40% of adults in the United States have reduced their consumption of fresh produce due to health concerns.
Professor David A. Relman of Stanford University explained that testing for microorganisms in the environment is far more complex than in human samples. He highlighted that the centralized production model, where lettuce from hundreds of farms is chopped and mixed together, creates an ideal environment for pathogens to spread widely.
According to The Washington Post, leafy greens are a leading cause of food poisoning. A 2024 analysis indicated that lettuce contributes to approximately 1.7 million cases of food poisoning annually in the United States, resulting in an economic loss of 3.7 billion USD, primarily due to the common practice of consuming it raw.
The CDC advises the public to wash hands with soap and thoroughly rinse all fruits and vegetables under running water before eating or cooking, including products labeled "pre-washed." For hard-skinned fruits and vegetables, such as cucumbers, the CDC recommends scrubbing them with a clean brush and cutting off any bruised or damaged parts.
However, washing only reduces the risk. Cooking food at a temperature of at least 70 degrees C can effectively kill parasites. Cut or cooked produce should be refrigerated within two hours.
Bao Nhien (According to Nytimes, Washington Post, Scientific American)
