Summary (tl;dr)

West Virginia has declared a statewide cyclosporiasis outbreak with 47 cases reported since mid-June 2026, contributing to a larger national surge of the parasitic illness across at least 31 U.S. states. Health officials are investigating the source of contamination, though no specific food item has been definitively identified for the overall outbreaks.

Essential Background

Cyclosporiasis is an intestinal illness caused by the microscopic parasite Cyclospora cayetanensis. Humans contract the infection by consuming food or water contaminated with feces containing the parasite. Direct person-to-person transmission is considered unlikely because the parasite requires several days to weeks in the environment to become infectious after being shed in stool. Symptoms, which typically manifest about one week after exposure, include watery diarrhea, loss of appetite, fatigue, stomach cramps, bloating, nausea, and a low-grade fever. If left untreated, the illness can persist from a few days to over a month, with symptoms potentially recurring. Past outbreaks in the United States have frequently been linked to contaminated fresh produce, such as raspberries, basil, snow peas, cilantro, and various salad mixes.

The Full Story

West Virginia health officials recently declared a statewide cyclosporiasis outbreak following a significant increase in reported cases. Since June 17, 2026, 47 cases have been identified across the state, which is a considerable rise compared to West Virginia's typical annual average of nine cases. This state-specific outbreak is part of a broader national trend, with the Centers for Disease Control and Prevention (CDC) reporting 843 confirmed domestically acquired cases across 31 states as of July 9, 2026. An additional 1,500 cases are undergoing further analysis to confirm domestic acquisition. The median onset date for illnesses nationally was June 18, 2026, with cases occurring between May 1 and July 5. While 86 individuals have been hospitalized across the U.S., no deaths have been reported. Currently, no single produce grower, supplier, or food item has been definitively identified as the source for the West Virginia outbreak or the wider national clusters. However, Michigan health officials have indicated that lettuce and salad greens are a "potential source" for the thousands of cases reported in their state. Other states like Ohio and New York are also experiencing unusually high numbers of cases.

Why It Matters

The surge in cyclosporiasis cases in West Virginia and across the nation is a significant public health concern due to the widespread nature of the gastrointestinal illness. Although cyclosporiasis is typically not life-threatening, it can lead to severe and prolonged watery diarrhea, requiring medical attention and, in some instances, hospitalization, as evidenced by 86 hospitalizations nationally during the current outbreak. The difficulty in pinpointing a common source for these outbreaks, partly because the parasite is hard to trace and sheds inconsistently, underscores the challenges in controlling its spread and highlights the critical importance of rigorous food safety practices for consumers and producers alike.

Geographic Location

• West Virginia, United States (statewide cyclosporiasis outbreak declared, 47 cases reported)
• Charleston, Kanawha County, West Virginia, United States (West Virginia health officials declared statewide outbreak)
• Hancock County, West Virginia, United States (Hancock County Health Department reported statewide outbreak)
• Wheeling, Ohio County, West Virginia, United States (Wheeling-Ohio County Health Department issued health advisory)
• Michigan, United States (state reporting thousands of cases, lettuce/salad greens identified as potential source)
• Ohio, United States (state reporting unusually high cases)
• New York, United States (state reporting unusually high cases)
• Illinois, United States (state reporting high number of cases)
• Texas, United States (state reporting high number of cases)
• Georgia, United States (state reporting cases, though no specific outbreak identified within the state)