More than 400 people across 18 states have been infected with Cyclospora cayetanensis in an active U.S. outbreak, The New York Times reported on July 2, 2026 — significantly higher than the 145 confirmed cases across 17 states the CDC had formally logged as of June 30. The gap exists because cyclosporiasis surveillance has built-in delays: the parasite takes one to two weeks to cause symptoms, illness persists for weeks without treatment, and many cases remain unreported until stool tests come back and are submitted to state health departments.

The CDC's confirmed cases show illness starting May 1, 2026, and continuing through June — meaning the outbreak has been spreading for at least two months. Florida and Georgia are among the affected states, according to News4Jax. As of early July, the CDC listed Cyclospora as an active foodborne outbreak under investigation.

Cyclospora cayetanensis is a single-celled parasite that lives inside human cells. Infection causes cyclosporiasis: prolonged watery diarrhea, nausea, fatigue, and weight loss that can last weeks without treatment. The standard drug is trimethoprim-sulfamethoxazole. The parasite leaves the body in feces but is not immediately infectious — it needs days to weeks in the environment to become capable of infecting someone else. This means the outbreak came from contaminated food or water, not from person-to-person spread.

Historically, U.S. cyclosporiasis outbreaks trace back to imported fresh produce. Cilantro from Mexico has appeared in multiple large outbreaks since the 1990s; raspberries, basil, snow peas, and pre-packaged salads have also been implicated. The timing here — cases beginning in early May and building through June — fits the pattern of spring and early-summer produce cycles. So far, no specific food source or supplier has been publicly named in connection with this 2026 outbreak.

The gap between 145 confirmed cases and 400-plus reported cases matters. CDC counts are confirmed through laboratory tests reported by state health departments; the higher number likely includes probable cases, cases still under investigation, or counts from a broader set of local sources. Neither figure is final. Active surveillance typically lags the true size of a foodborne outbreak by weeks, and cyclosporiasis testing is inconsistent across hospitals and clinics.

For public health and food safety teams, speed is critical now. Traceback investigations — tracing food back to its source — work against a clock. Produce moves through supply chains rapidly, and the longer investigators wait, the harder it becomes to follow the paper trail. If the culprit is a high-volume product like cilantro or bagged salads, detailed records from distributors and stores become essential. The FDA, which oversees most produce linked to past outbreaks, has not publicly identified a source or issued a recall as of July 3, 2026.

The lack of a named source does not mean investigators are stalled. Most traceback work happens behind the scenes until officials have enough evidence to act. But if the 400-plus count holds, this outbreak would rank among the larger cyclosporiasis events in recent U.S. history. The 2013 multistate outbreak involved roughly 643 confirmed cases across 25 states; in 2018, over 2,000 cases emerged, ultimately traced to Del Monte Fresh Produce vegetable trays. The 2026 case count is still growing.

Doctors seeing patients with weeks of watery diarrhea — especially those who ate fresh herbs or produce recently — should test for Cyclospora using specialized stool exams, since standard bacterial cultures will not catch it.