DSU food safety experts explain what consumers should know about cyclosporiasis

As health officials continue monitoring cases of cyclosporiasis linked to contaminated food, Delaware State University food safety experts say understanding how the illness spreads, recognizing the symptoms and following safe food handling practices can help reduce the risk of infection.

Cyclosporiasis is caused by Cyclospora cayetanensis, a microscopic parasite that infects the small intestine. While many foodborne illnesses are caused by viruses and bacteria such as norovirus and Salmonella, parasites can also contaminate food and water.

Dr. Wilbert Long III, senior research scientist in food microbiology and food safety in Delaware State University’s Food Science Program, said Cyclospora is most commonly spread when food or water becomes contaminated with fecal matter containing the parasite. Because the parasite is destroyed by heat, fresh produce, including leafy greens, green onions and raspberries, is more commonly associated with infections because it is often eaten raw.

“Most foodborne illnesses are caused by viruses and bacteria such as norovirus and Salmonella,” Dr. Long said. “However, they are not the only causes of foodborne illnesses, and parasites may also cause such illnesses.”

People infected with Cyclospora typically develop symptoms within about one week, although illness can appear up to two weeks after exposure. According to Dr. Long, common symptoms include watery or explosive diarrhea, stomach cramps, digestive changes and fatigue. Some people may also experience vomiting, headaches, body aches or a low-grade fever.

Treatment commonly includes antibiotics, along with supportive care such as replacing fluids lost through diarrhea and vomiting. Dr. Long said anyone who experiences diarrhea or other severe symptoms lasting longer than three days after eating potentially contaminated food should contact a healthcare provider. He also noted that one common misconception is that cyclosporiasis spreads easily from person to person. Because the parasite requires at least one to two weeks in the environment before it becomes infectious, direct person-to-person transmission is considered extremely unlikely.

To help reduce the risk of infection, Dr. Long recommends washing all fresh produce under clean running water, even if it will be peeled. Firm fruits and vegetables, such as melons and cucumbers, should be scrubbed with a clean produce brush, and any bruised or damaged areas should be cut away before preparing or eating them. He also emphasizes washing hands with soap and water before and after handling food, thoroughly cleaning and sanitizing cutting boards, utensils, countertops and other food preparation surfaces, and refrigerating cut, peeled or cooked fruits and vegetables as soon as possible.

While safe food handling at home is important, preventing contamination before food reaches the dinner table is equally critical, according to Dr. Jung-lim Lee, professor of Food Science and Biotechnology in Delaware State University’s College of Agriculture, Science and Technology.

Dr. Lee said Cyclospora and Giardia are the two parasites most commonly associated with food contamination, with infections typically occurring through contaminated food or water. Dr. Lee explained that protecting the food supply requires a “farm-to-fork” approach that begins with good agricultural practices and continues through harvesting, packaging, transportation, retail handling and food preparation at home.

“Most people think food is safe as long as farmers follow good agricultural practices or it has been inspected by the USDA,” Dr. Lee said. “However, there are still significant opportunities for bacterial, viral and other microbial contamination during post-harvest, throughout processing, packaging, transportation, retail and ultimately to consumers’ tables.”

Dr. Lee said reducing the risk of foodborne illness requires attention at every stage of the food supply chain, from farms and food processors to grocery stores and consumers’ kitchens. Dr.Lee added that recovery from cyclosporiasis can vary depending on a person’s immune system, age and underlying health conditions.

Advances in DNA-based testing, including PCR technology, have also improved the detection of Cyclospora, helping investigators identify contamination more quickly. Dr. Lee encourages consumers to stay informed by following food recalls and food safety updates from the U.S. Food and Drug Administration and the Centers for Disease Control and Prevention.