Health authorities in the United States announced on Wednesday that cases of Cyclospora infection have been associated with iceberg lettuce across 15 states, an increase from the previous count of nine states. This announcement follows the identification of six additional states that are experiencing cases related to the current outbreak.
So far this year, the parasite has been detected in at least 47 states, and investigations are ongoing to determine the extent of cases that may be connected to a shared contaminated source.
The Centers for Disease Control and Prevention (CDC) reported the updated figure, listing Arkansas, Iowa, Missouri, Nebraska, New Hampshire, and North Carolina among the affected states. They join Illinois, Indiana, Kansas, Kentucky, Michigan, Ohio, Oklahoma, Pennsylvania, and West Virginia.
Initially, the focus of the investigation was on the lettuce served at Taco Bell. However, federal officials later identified Taylor Farms as the key supplier of the implicated lettuce, prompting a recall of iceberg lettuce sourced from central Mexico.
Last month, there was confusion when the Food and Drug Administration (FDA) stated that a sample of lettuce from Taylor Farms that had tested positive for Cyclospora was later deemed a false positive. The following day, the FDA reaffirmed that the investigation continues to indicate shredded iceberg lettuce from Taylor Farms in central Mexico as the likely source of the outbreak.
Dr. Ulysses Wu, the chief epidemiologist at Hartford HealthCare, expressed concerns to CBS News last month, stating, “I don’t think we can say that this is under control yet. Even if this lettuce was implicated, it doesn’t mean that other produce is not implicated as well.”
The CDC previously mentioned that it may take up to six weeks for health officials to confirm whether a sick individual is part of an outbreak. Dr. Juan Luis Marquez, the medical director for the Washtenaw County and Livingston County health departments in Michigan, explained that several factors complicate the investigation and containment of Cyclospora outbreaks. The time gap between exposure and symptom onset, the challenges in laboratory analysis of the parasite, and the extensive effort required to interview affected individuals are all contributing factors. Dr. Marquez, who also teaches public health at the University of Michigan, noted staffing shortages across public health sectors at federal, state, and local levels, which have reduced available resources.
Cyclospora is a microscopic, round parasite known to cause watery diarrhea, often accompanied by frequent and sometimes severe bowel movements, according to the CDC. These outbreaks typically occur during late spring and summer months.
This heat-loving parasite affects the intestines and spreads through fecal contamination. The resulting illness, known as cyclosporiasis, is less frequently reported than foodborne illnesses caused by other pathogens, such as salmonella and E. coli. Many cases of Cyclospora are not traced back to any specific food source.
The year with the highest recorded infections in the U.S. was 2019, with approximately 4,700 illnesses reported nationwide. However, this year has already seen a significant spike, with Michigan alone reporting over 12,000 cases, including two fatalities. When accounting for cases in other states, the national total exceeds 25,000.
As of July 30, local health officials reported that among the over 12,000 cases in Michigan, 193 individuals required hospitalization. The Michigan Department of Health and Human Services indicated that the two individuals who died had “significant underlying health conditions.”
The FDA is monitoring five separate Cyclospora outbreaks currently in progress, with the outbreak affecting 15 states being the most substantial. No specific products have been identified in connection with the other outbreaks, which have collectively sickened 115 individuals.
