Parasitic Outbreak in the Midwest Raises Health Concerns

A parasitic outbreak causing severe diarrhea is spreading across the Midwest. Health officials warn it could be weeks before they identify the source. As of July 13, over 3,000 cases of cyclosporiasis, an illness caused by the Cyclospora cayetanensis parasite, are reported in Michigan and Ohio. Additional cases are linked to West Virginia and Kentucky. Nationally, the Centers for Disease Control and Prevention (CDC) confirm more than 7,000 cases across 34 states since May 1.

Investigating the Source

Michigan health officials suspect lettuce or salad greens may be behind the outbreak, though other foods are not ruled out. CDC investigators are gathering extensive data to resolve this outbreak. Federal officials expect the outbreak could continue through August as contamination is traced through the supply chain. While cyclospora garners attention, it is not the only parasite found in everyday fruits and vegetables.

Insights from Experts

Jason Reese, a food safety expert and co-founder of Wagner Reese LLP, shared insights with Newsweek about the outbreak. He noted the challenge of tracing cyclospora as it spreads through contaminated fecal matter reaching food or water. The contamination usually occurs at farms or during processing. Possible causes include tainted irrigation, inadequate worker hygiene, or supply chain issues.

Reese warned of an increase in cases during warmer months. He advised caution with produce like bagged salads, herbs, green onions, snow peas, leafy greens, and raspberries. Contamination is often invisible and may take a week to show symptoms, making it hard for individuals to trace their illness to a specific meal.

Other Parasites to Be Aware Of

Jill Roberts, a microbiologist and professor at the University of South Florida College of Public Health, discussed four parasites, including cyclospora, with Newsweek.

Cyclospora

Cyclospora is common in imported produce. Past outbreaks linked it to basil, cilantro, snow peas, and berries. Washing may remove about 80% of the pathogen, but only cooking eliminates it. Though usually not dangerous, dehydration is a concern.

Cryptosporidium

This parasite is mostly found in water and produce washed with contaminated water. Resistant to chlorine, it must be filtered from drinking water. Cooking kills it. Cryptosporidium can be deadly for those with weakened immune systems. The worst outbreak occurred in Milwaukee in 1993 due to a treatment plant failure.

Giardia

Like cryptosporidium, Giardia spreads through water and produce washed with contaminated water. It is chlorine-resistant but can be filtered and is killed through cooking. Though rarely dangerous, prolonged diarrhea should be checked by a doctor. It’s commonly found in pets and can spread to humans.

Toxoplasma gondii

Toxoplasma is linked to undercooked meat, particularly pork, as well as shellfish and contaminated produce. Cooking to proper temperatures kills it; washing is only partially effective. While most infections are mild, it can cause severe health issues. Pregnant women should avoid changing cat litter due to the risk of spread. Toxoplasma is a leading cause of foodborne illness-related death.