Cyclospora Outbreak Prompts Warning Against Bagged Salads

A former head of food safety at the Food and Drug Administration (FDA) urges caution regarding bagged salads as cyclospora infections rise across the nation. Susan Mayne, an epidemiology professor at Yale and former director of the FDA’s Center for Food Safety and Applied Nutrition, advised consumers during a CBS News interview to avoid prepackaged leafy greens. This warning is part of an ongoing probe into a widespread cyclosporiasis outbreak caused by the parasite Cyclospora cayetanensis.

The parasite, often linked to fresh goods like leafy greens, herbs, and berries, results in severe watery diarrhea, cramping, and fatigue. While the source of the outbreak remains unidentified, experts recommend extra caution with high-risk foods.

Newsweek contacted the FDA and CDC for comments.

The Cyclospora Surge

The Centers for Disease Control and Prevention (CDC) reports 4,173 confirmed cyclosporiasis cases since May and 7,400 unconfirmed instances. State counts often exceed this number, with Michigan reporting 8,176 cases. The outbreak is among the largest recorded in the U.S. Earlier, a cluster of 1,947 illnesses in nine states was related to Taylor Farms’ shredded iceberg lettuce.

In response, a Taylor Farms representative stated, “There are no confirmed positive Cyclospora test results as of July 24, 2026.” The company emphasized food safety, detailing over $200 million annual investments in prevention protocols. When concerns arose, they withdrew potentially affected products and initiated a wider recall of iceberg lettuce sourced from Central Mexico.

Taylor Farms engaged independent experts for reviewing safety measures at its Central Mexico site, suspended production there since July 18.

The FDA is investigating another cyclospora outbreak, not yet traced to a specific item, with lettuce, parsley, and cilantro being primary suspects.

FDA Advice on Bagged Salads

Despite Taylor Farms’ recall actions, Mayne continues advising against bagged salads. She noted, “We’ve never seen anything like this,” describing the event as a record-setting outbreak. She explained that minimal contamination spreads more easily through bagged salads.

This outbreak highlights flaws in federal monitoring of foodborne illnesses. Mayne cited underfunded U.S. food safety efforts. In July 2025, Foodborne Diseases Active Surveillance Network (FoodNet), a collaboration between the CDC, state health departments, and the USDA, reduced its tracking program for infections like cyclospora. U.S. Department of Health and Human Services Secretary Robert F. Kennedy, Jr. claimed only redundant programs were cut, but Mayne disagreed, affirming cutbacks.

Understanding Cyclospora

Cyclospora, a parasite called Cyclospora cayetanensis, causes cyclosporiasis, an intestinal condition. Infection occurs after ingesting contaminated food or water, typically where fresh produce encounters fecal contamination. Mayne mentioned inadequate hand-washing facilities and other contamination sources. Symptoms include prolonged diarrhea, severe cramps, nausea, bloating, weight loss, fatigue, loss of appetite, and recurring gastrointestinal issues. Symptoms start up to two weeks post-exposure and can persist for months without treatment.

Cyclospora is not commonly transferred between individuals directly, as the parasite requires environmental maturation to become infectious, complicating outbreaks. Treatment usually involves the antibiotic trimethoprim-sulfamethoxazole, or Bactrim. Though most people fully recover, severe dehydration and lengthy illness can occur, especially in vulnerable groups.

More Resources and Information

For additional information, readers can explore stories on cyclospora testing, symptoms, safe salad greens, treatment, and protective measures. Newsweek editors Steve Mollman and Anthony Murray are available for contact regarding this story.