How to clean lettuce during a cyclospora outbreak
USA TODAY’s Mike Snyder demonstrated how to properly clean and store leafy greens.
Salad lovers champion lettuce as a staple of a healthy diet. But what do you do when munching on leafy greens becomes a food safety risk due to an outbreak of cyclosporiasis, which can cause painful diarrhea?
A healthy diet includes fruits and vegetables, but unfortunately, fresh foods can become contaminated with bacteria such as E. coli and the parasite Cyclospora.
As crops grow, they can become contaminated by toxic substances in the water or soil, or by the feces of infected people. Even after produce is harvested, many people handle it, increasing the risk of contamination, the Food and Drug Administration says.
According to the Centers for Disease Control and Prevention, the parasite (official name Cyclospora cayetanensis) is an oocyst, an organism that lives on or inside another organism and can be excreted in feces (poo) and contaminate water used for irrigation and cleaning. It can then be transmitted to others through the food chain.
Washing lettuce reduces the risk, but removing cyclospora from produce is not easy, said Dr. Tyler Evans, founder of the Wellness Equity Alliance and former New York City chief medical officer.
“Washing produce takes the load off and is worth doing,” Evans told USA TODAY. “However, Cyclospora lives on a tough, sticky shell that clings to the crevices of leafy vegetables and the fine hairs of berries, and the CDC is clear that routine chemical disinfection and disinfection will not kill it.”
Shredded iceberg lettuce is the only produce currently identified as likely to be contaminated during the current outbreak. Although you can’t eliminate all risks, washing lettuce properly will make for a healthier salad. This should be standard food safety practice.
“Good hand hygiene and safe food preparation practices are always important,” said Dr. Shira Mada, an infectious disease epidemiologist at Harvard Kennedy School’s Belfer Center for Science and International Studies. “Otherwise, there is no reason to broadly avoid lettuce and other raw vegetables.”
In many foods, heating to at least 158 degrees will kill parasites, but “for produce that is eaten raw, we need to avoid products that have been specifically identified by public health officials during the outbreak, rather than assuming that they are safe if washed,” he said.
The correct way to wash lettuce
Kelsey Holloman, manager of the Foodborne Disease Epidemiology Program at the Virginia Department of Health, said leafy greens and produce should always be washed under running water before cutting, cooking or eating. “I advise people to always remain vigilant.” Here are her tips on how best to wash lettuce.
- Wash your hands, as well as your cooking utensils and cutting boards. “Wash your hands thoroughly with soap and water, especially before and after preparing meals and after using the bathroom or changing diapers,” Holloman said. Knives and cutting boards must be clean and disinfected.
- Discard the outer leaves of the lettuce. Discard the outer leaves and any torn or bruised leaves, along with the head of iceberg lettuce or romaine.
- Wash the lettuce leaves thoroughly. Gently rub the surface of each leaf with your hands to remove sand and dirt. For example, iceberg lettuce is more tightly packed than romaine or Boston lettuce, so instead of washing each leaf individually, you can cut it in half and soak the center under running water for a few minutes.
- Dry the lettuce. Even if you use a salad spinner to dry your lettuce, you should dry it with a clean cloth or paper towel afterwards.
Even if the lettuce you buy says it’s pre-washed, “you still need to rinse it with clean water when you get home,” Holloman says.
Should I eat lettuce?
Michigan is the state with the most reported cases of cyclosporiasis. USA TODAY contacted the Michigan Department of Health and Human Services, which says residents should “purchase whole lettuce rather than pre-washed and bagged lettuce or pre-mixed salad kits.”
Dr. Susan Chen, associate dean for public health practice at Tulane University’s Celia Scott Weatherhead School of Public Health and Tropical Medicine, said the current risk of strongyloid contamination is low because produce from local farmers markets is typically not shipped nationally.
However, if you’re pregnant, you may want to avoid fresh leafy greens, herbs, and berries for a while, Chen says.
“In the meantime, make sure all produce is well-cooked or has peels that can be peeled after washing well first (oranges, mangoes, melons, bananas, etc.).”
Mike Snyder is a national trends news reporter for USA TODAY. You can follow him on Threads, Bluesky, and X, and email him at:mike snyder & @mikegsnider.bsky.social & @mikesnider & msnider@usatoday.com.
