The recent cyclospora outbreak has drawn attention to a wider issue of foodborne illnesses, but experts emphasize that cyclospora is not the sole pathogen to monitor. Dr. Jill Roberts, an expert in public health at the University of South Florida, highlights five additional foodborne pathogens—listeria, shigella, enterohemorrhagic E. coli, vibrio, and yersinia—that have seen increased activity in the U.S. recently. Improved lab detection partly explains the rise, but each pathogen spreads through unique routes requiring specific solutions.

Concerns About Listeria

Dr. Roberts expresses significant concern regarding listeria, particularly due to the strain on systems designed to detect outbreaks early. Listeria has been responsible for two of the deadliest outbreaks in U.S. history, related to cantaloupe and queso fresco. The CDC’s PulseNet network played a crucial role in stopping these outbreaks, but both it and state labs are struggling with resource issues. Listeria surveillance under CDC’s FoodNet program ceased last year.

Roberts: “Listeria is the pathogen I am most worried about currently.”

Details on Listeria

Listeria monocytogenes can contaminate ready-to-eat foods like soft cheeses and deli meats. Infections can lead to serious conditions like meningitis or death, especially in vulnerable groups such as pregnant women and older adults. A notable 2025 outbreak linked to pasta meals sold at major retailers affected 28 people across 19 states, resulting in 27 hospitalizations and seven deaths.

Shigella

Shigella causes shigellosis, characterized by diarrhea, fever, and stomach cramps. Its low infectious dose allows easy spread between people and through contaminated food. The CDC warns of rising drug-resistant Shigella strains, which accounted for 8.5% of cases in 2023.

Challenges with Shigella

Roberts notes Shigella’s ability to infect populations lacking clean food and water access, such as the homeless community.

Enterohemorrhagic E. Coli

Enterohemorrhagic E. coli, including O157:H7, releases toxins causing severe gastrointestinal symptoms. Complications include hemolytic uremic syndrome leading to kidney failure. In 2026, a raw dairy product outbreak affected nine individuals in three states.

Mitigation Strategies for E. Coli

Roberts advocates for stricter rules on irrigation water and banning raw milk products.

Vibrio

Vibrio bacteria thrive in warm coastal waters, sometimes causing severe skin infections akin to “flesh-eating” conditions. Florida reported multiple Vibrio infections linked to raw oysters, emphasizing the need for high-risk individuals to avoid them.

Yersinia

Yersinia enterocolitica primarily infects through raw pork, causing fever and abdominal pain. Vulnerable groups include young children and older adults.

Fighting Yersinia

Roberts suggests ensuring proper cooking temperatures and banning raw milk products to combat its rise.

Norovirus

Despite other pathogens’ concerns, norovirus remains the leading cause of foodborne illness, responsible for over half of cases. Its activity typically surges from October through winter.

For inquiries, Newsweek editors Kara Dolman and Gray R. Thomas are available.