US Cyclospora Outbreak Targets 'Healthy' Eating: About 3,000 Cases Linked to Salads and Fresh Produce

As of Friday 10 July 2026, data compiled from the US Centres for Disease Control and Prevention and state health departments indicated 2,944 reported cyclosporiasis cases across 32 states. Officials and national outlets are describing the total as 'nearly 3,000' illnesses linked to this season's outbreak.

The fast-moving outbreak is widely associated with salads and fresh produce, turning the summer's 'healthy' eating habits into a source of anxiety. Michigan has recorded the sharpest spike, with 2,640 cyclosporiasis cases and at least 44 hospitalisations reported by the evening of 13 July. Health officials there are now pointing to lettuce and salad greens as a potential source, while stressing that the investigation is ongoing and no single grower or supplier has been identified.

The illness is caused by the microscopic Cyclospora cayetanensis parasite, which spreads when people ingest food or water contaminated with faeces. It can trigger weeks of watery and sometimes explosive diarrhoea, cramps, bloating, loss of appetite and fatigue.

Suspected Source: Lettuce and Salad Greens

Cyclospora is most often linked to fresh produce eaten raw or only lightly handled, because washing can reduce but not entirely remove contamination. Previous US outbreaks have been tied to bagged salad mixes, salad kits, raspberries, basil, coriander and other ready-to-eat vegetables. Regulators have documented large incidents specifically tied to bagged salads containing lettuce and other greens.

In Michigan, officials say interviews with many patients repeatedly highlight lettuce and salad greens as a common food exposure, echoing patterns seen in those earlier outbreaks.

For weeks this summer, investigators were unable to name any specific food beyond that historical fresh-produce pattern. That changed in mid-July, when Michigan's chief medical executive said 'early information has shown lettuce as a common product that regularly comes up during the investigation.' A state news release similarly reported that 'current results point to lettuce or salad greens as a potential source' of the outbreak.

Officials cautioned that the source is not yet definitive. Other foods, including raspberries and herbs, have not been ruled out, and no brand or supplier has been identified.

Official advice for consumers

The Michigan Department of Health and Human Services has issued specific guidance in response:

• Buy whole heads of lettuce rather than pre-washed salad mixes
• Discard the outer two or three layers of leaves
• Wash inner leaves thoroughly under running water
• Heat leafy greens to at least 70°C when cooking is an option
• Wash herbs such as basil and coriander leaf by leaf, and cook them when possible
• Wash all fruit and vegetables thoroughly before cutting, cooking or eating

Nationally, health authorities and the CDC have updated clinical guidance to reflect rising case numbers and the difficulty of detecting Cyclospora with routine tests. Clinicians are urged to specifically request stool testing for the parasite when patients present with prolonged watery diarrhoea, especially in summer or after eating raw salad, herbs or fruit. Repeat specimens are recommended, since Cyclospora may be shed intermittently.

The standard treatment is a course of trimethoprim-sulfamethoxazole antibiotics, which can shorten illness and reduce relapses.

Anyone experiencing persistent diarrhoea for more than a few days, particularly after eating raw leafy greens, herbs or berries, should seek medical advice and mention possible exposure to Cyclospora. Patients are encouraged not to be embarrassed about describing 'explosive' bowel movements, bloating and fatigue. These details help clinicians recognise cyclosporiasis and help health departments trace contaminated produce.

Officials stress that people should not abandon fruit and vegetables altogether. Thorough washing, careful handling and attention to official updates can keep plant-rich diets central to 'healthy' eating, even as this summer's outbreak exposes weaknesses in how that food reaches the plate.