UNIVERSITY PARK, Pa. — Dubbed the “nightmare stomach bug,” with nearly 7,000 currently confirmed or suspected cases of cyclosporiasis in several U.S. states, including Pennsylvania, many consumers may be wondering how to protect themself from the foodborne illness, which is caused by the microscopic parasite cyclospora and includes symptoms like diarrhea, nausea and fatigue.
In this Q&A, experts from Penn State Extension and Penn State’s College of Agricultural Sciences discussed the outbreak, preventing infection and what to do if experiencing symptoms.
Q: What is cyclospora and what are the symptoms?
Nicole McGeehan, food safety extension educator: Cyclospora is a microscopic parasite that can contaminate fresh produce through contact with human waste and/or contaminated water during growing, harvesting or processing. Unlike many foodborne illnesses, cyclospora is not typically spread directly from person to person because the parasite must first mature in the environment before it becomes infectious.
Symptoms usually begin about one week after eating contaminated food, although they may appear anywhere from two days to two weeks after exposure. Common symptoms include:
- Frequent watery diarrhea
- Loss of appetite
- Weight loss
- Stomach cramps or bloating
- Nausea
- Fatigue
- Low-grade fever
Without treatment, symptoms may last for several weeks or longer. Some people experience symptoms that improve and then return. Anyone experiencing prolonged diarrhea should contact a healthcare provider, as laboratory testing is required for diagnosis of a cyclospora infection. People can be infected with cyclosporamore than once.
Q: How can you reduce your risk of getting cyclosporiasis?
Luke F. LaBorde, professor emeritus of food science and extension specialist: Health officials have indicated that lettuce and salad greens are a potential source, although at this time other foods have not been ruled out. Penn State Extension recommends following safe food handling practices to reduce the risk of foodborne illness:
- Wash hands with soap and water for at least 20 seconds before and after handling fresh produce.
- Rinse all fruits and vegetables thoroughly under cool, running water before eating, cutting or cooking.
- Gently rub firm produce, such as apples, cucumbers and melons, while rinsing. Use a clean produce brush when appropriate.
- Remove and discard the outer leaves of leafy vegetables, including lettuce and cabbage.
- Use separate cutting boards for fresh produce and raw meat, poultry and seafood to prevent cross-contamination.
Q: Can washing remove cyclospora? What about cooking?
Kaitlin Pander, food safety extension educator: According to the Centers for Disease Control and Prevention (CDC), there is currently no method known to completely eliminate cyclospora from contaminated fresh produce. Washing fruits and vegetables under clean, running water cannot guarantee removal of the parasite, but it remains an important food safety practice because it removes dirt and may reduce other contaminants. The CDC and Penn State Extension continue to recommend rinsing all fresh produce before eating, cutting or cooking.
The U.S. Food and Drug Administration states that cooking foods to at least 158 degrees Fahrenheit is required to inactivate the parasite. However, many of the fruits and vegetables associated with cyclospora outbreaks — such as leafy greens, herbs and berries — are typically eaten raw. For produce that is consumed fresh, continue following recommended food safety practices, including rinsing it under clean, running water and monitoring CDC and U.S. Food and Drug Administration updates as the outbreak investigation continues.
Additionally, while social media often promotes soaking fruits and vegetables in vinegar, baking soda or commercial produce washes during foodborne illness outbreaks, there is no scientific evidence that these methods destroy or eliminate the cyclospora parasite.
Q: Should consumers avoid fresh produce if they want to protect themselves from cyclosporiasis?
McGeehan and: No. Fresh fruits and vegetables remain an important part of a healthy diet and provide essential vitamins, minerals and dietary fiber. Unless public health officials identify a specific food linked to the outbreak, consumers should continue eating a variety of fresh produce while following recommended food safety practices.
Pander: As investigators work to identify the source of the current outbreak, consumers are encouraged to monitor updates from the CDC. If a contaminated food item is identified, public health officials will provide additional guidance and, if necessary, recall information.
Q: Can shopping locally at small farms or farmers’ markets help lower risk of cyclosporiasis?
Jeffrey Stoltzfus, farm food safety extension educator: Small farms are no less likely to have contaminated produce. However, consumers at farmers markets are more likely to know where their produce is being grown, so when large outbreaks occur in other states, it is unlikely to affect the produce they have purchased.
LaBorde: However, food safety behaviors — not location — are important, such as not allowing workers with symptoms to handle food, adhering to proper handwashing practices, and using uncontaminated pre- and post-harvest agricultural water supplies. Transmission comes from infected humans; toilets and handwashing facilities; workers’ boots, clothing and gloves; tools and equipment; sewage systems; and agricultural water sources and distribution systems. So, contamination can happen on any farm, large or small, farmers markets or supermarkets.
Learn more
For the latest information about the ongoing cyclospora outbreak, visit the CDC’s cyclosporiasis webpage. For additional guidance on selecting, storing and preparing fresh produce safely, visit Penn State Extension’s page on Proper Care and Handling of Fruits and Vegetables. Extension also offers food safety workshops that teach growers how to prevent crop contamination.
