The cyclosporiasis outbreak in USA continues to grow as the Centers for Disease Control and Prevention (CDC) announced that 1,645 domestically acquired cases have been confirmed across 34 states, with more than 5,100 additional cases currently under investigation.
The illnesses are tied to Cyclospora, a microscopic, foodborne parasite that infects the small intestine and causes prolonged gastrointestinal distress. Federal health officials have confirmed a large multistate outbreak involving at least four Midwestern states—Michigan, Ohio, West Virginia, and Kentucky—where over 400 cases appear to be linked.
While initial data from Michigan health officials indicate that lettuce or salad greens are a potential source of the Cyclosporiasis outbreak in USA, a specific grower, supplier, or definitive food source has not yet been confirmed nationwide. Public health authorities are monitoring the situation with heightened urgency, as late spring and summer mark the peak seasonal window for this specific pathogen.
CDC Reports Surging Cyclospora Infection Cases In US
According to the latest surveillance figures released by the CDC, the cyclosporiasis outbreak in USA has seen a massive rise in numbers.
The tracking data outlines the scope of the domestic cases:
- Confirmed Domestic Cyclospora Cases: 1,645 individuals across 34 states who reported no international travel prior to falling ill. More than 5,100 additional illnesses are currently being evaluated.
- Hospitalizations & Deaths: About 1 in every 11 cases were hospitalized; 0 deaths.
- Illness Onset Period: May 1, 2026, through mid-July 2026.
- Patient Demographics: Affected individuals range in age from 5 to 86 years old. Ongoing patient data collection for age, race, ethnicity, and food history to pinpoint the source.
Public health officials emphasize the distinction between these domestically acquired cases and travel-associated infections. The primary focus remains on the domestic food supplies causing the cyclosporiasis outbreak in USA.
Officials Investigate the Source of US Cyclosporiasis Cases
The CDC, the Food and Drug Administration (FDA), and individual state health departments are collecting various data points and conducting traceback investigations on suspect food items to discover where potential contamination occurred. Donald Prater, the FDA’s Acting Deputy Commissioner for Food, confirmed that the agency is actively analyzing locations reported by patients before they became ill.
Amid these inquiries, Taco Bell announced it has voluntarily and temporarily removed limited ingredients at select restaurants as a precautionary measure. In a corporate statement, Taco Bell emphasized that public health officials have not confirmed a link between the outbreak and any specific ingredient, supplier, restaurant, or retailer. However, “The health and safety of our guests is our top priority,” it said.
Because many people suffering from gastrointestinal issues recover at home without seeking medical testing, surveillance data is expected to shift as more laboratory-confirmed Cyclospora infection cases in US are funneled into the national database.
Which States Are Affected by Cyclospora Infection?
The 1,645 domestic Cyclospora cases are distributed across 34 states.
- Michigan has emerged as the hardest-hit area, reporting a staggering 3,309 cases under local investigation as of mid-July 2026.
- Ohio, West Virginia, and Kentucky are also experiencing high case volumes tied directly to the prominent Midwestern cluster of diarrhea outbreaks.
- Other Confirmed States with Cyclospora Outbreak: New York, Illinois, Texas, Alaska, Colorado, Connecticut, Florida, Georgia, Louisiana, Massachusetts, New Jersey, North Carolina, Pennsylvania, Tennessee, Virginia, and Wisconsin, among others.
While the CDC continues its broader investigation, local health departments are tackling localized surges. Because the true number of sick people is likely much higher than official reports indicate, public health teams are urging individuals with sudden, persistent diarrhea to seek immediate medical care.
What Is Cyclospora and How Does It Infect People?
Cyclospora cayetanensis is a microscopic, single-celled parasite, spread through the consumption of food or water contaminated with infected feces. Once ingested, the parasite settles into the small intestine, disrupting normal digestion.
The rising temperatures could expand the cyclosporiasis outbreak in USA, as the Cyclospora parasite thrives in humid climates, making May through August the primary window for seasonal spikes.
Historically, similar outbreaks have been tied to imported fresh produce. In the current investigation of the parasitic diarrhea outbreak in USA, early data points heavily toward lettuce or salad greens, though other food items cannot be entirely ruled out, according to MDHHS.
What Are The Symptoms of the Diarrhea Parasitic Infection?
The Cyclospora parasitic infection differs significantly from standard, short-lived stomach viruses. Unlike norovirus, which typically resolves in 48 hours, Cyclospora symptoms persist for weeks if left untreated.
Common Gastrointestinal Symptoms:
- Watery, often explosive diarrhea
- Frequent, urgent bowel movements
- Severe abdominal cramps and bloating
- Increased gas and nausea
- Loss of appetite and subsequent weight loss
- Pervasive fatigue
Less Common Cyclospora Symptoms:
- Vomiting
- Low-grade fever
- Headaches and generalized body aches
Without appropriate medical treatment, symptoms can cyclically disappear and return over several months, resulting in prolonged fatigue and physical exhaustion.
Seek immediate medical care if anyone experiences the symptoms of Cyclospora infection.
How to Protect Yourself During the Cyclospora Parasite Outbreak?
The surging cyclosporiasis outbreak in USA highlights the critical importance of food safety and active public health surveillance. Because the parasite is highly resistant to chemical sanitizers such as chlorine, standard washing alone may not completely eliminate the risk posed by delicate fresh items.
Given the potential link to salad greens, health officials have issued specific preparation guidelines:
- Purchase Whole Heads: Buy whole heads of lettuce rather than pre-washed, bagged lettuce or pre-mixed salad kits.
- Discard Outer Layers: Before preparation, remove and discard the outer two to three layers of leaves.
- Wash Inner Leaves Thoroughly: Rinse the remaining inner leaves under clean running water.
- Prioritize Cooking: For greens that can be cooked, heating them to an internal temperature of at least 158°F (70°C) is the safest option.
- Wash Hands Thoroughly: Use soap and warm water for at least 20 seconds before and after handling raw food.
