Cyclospora 

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Latest news on Cyclospora, covering the US outbreak, cyclosporiasis symptoms, food recalls, treatment, and case updates nationwide.

Cyclosporiasis is an intestinal illness caused by Cyclospora cayetanensis, a microscopic parasite too small to see without a laboratory microscope. The main symptom is watery, sometimes explosive, diarrhoea, alongside nausea, cramping, bloating, fatigue and weight loss. People become infected by consuming food or water contaminated with the parasite, usually through fresh produce, rather than through contact with another infected person. The Centers for Disease Control and Prevention and the Food and Drug Administration lead surveillance and traceback efforts whenever case numbers rise.

The United States is experiencing its largest recorded cyclosporiasis outbreak this year, with laboratory-confirmed domestic cases running many times higher than the same period in recent years. A major multistate cluster has been linked to shredded iceberg lettuce supplied from central Mexico, prompting a voluntary recall and warnings against eating the affected product, including at fast-food restaurants that used it. Nearly every state has reported cases, with the Midwest, and Michigan in particular, among the hardest hit. Health officials have confirmed hospitalisations and a small number of deaths among people with serious underlying conditions, though case numbers have begun to ease in some of the worst-affected areas.

Recovery from cyclosporiasis can take weeks without treatment, and doctors typically prescribe a course of antibiotics to clear the infection. Anyone with persistent watery diarrhoea after eating fresh produce is generally advised to contact a doctor for stool testing, since diagnosis can require several samples taken over different days. Consumers are encouraged to check the origin of bagged salads, herbs and other raw produce, and to ask restaurants about ingredient sourcing during active outbreaks. Food safety agencies continue to update guidance as investigations into contaminated supply chains progress.

Cyclospora was first recognised as a significant human pathogen only in recent decades, and it remains endemic in many tropical and subtropical countries. Earlier US outbreaks have been traced to raspberries, fresh basil, cilantro, snow peas and mesclun lettuce, usually imported from regions where the parasite is more common. Case numbers typically climb each year between May and August, a pattern consistent enough that health authorities treat it as the annual cyclosporiasis season. Repeated exposure in endemic regions appears to build some natural resistance, with symptoms tending to be milder in adults than in young children.

Tracking Cyclospora is harder than tracking many bacterial pathogens, since whole genome sequencing is not yet widely available for this parasite, slowing efforts to pinpoint contaminated food sources. The illness is also widely believed to be underdiagnosed and underreported, meaning official case counts likely understate the true scale of any outbreak. The parasite resists routine chlorine disinfection, complicating water treatment and hospital infection control. Recurring links to imported fresh produce have also renewed scrutiny of supply chain oversight and traceback speed during multistate investigations.

Stay across the latest cyclosporiasis case counts, food recalls and health guidance with NewsNow's dedicated Cyclospora feed, updated as new developments emerge.