Is There an End in Sight to the Cyclosporiasis Outbreak?

Will the Outbreak Be Over Soon?

The outbreak isn’t likely to end anytime soon, says John Sellick Jr., DO, an infectious disease expert and epidemiological researcher at the State University of New York at Buffalo. “There are probably a couple of different outbreaks going around. We already know that iceberg lettuce is an issue, but it wouldn’t be surprising if other contaminated produce shows up as well.”

The iceberg lettuce implicated in the outbreak has already been recalled and pulled from the market. But reported cases of cyclosporiasis are likely to go up.

Symptoms of cyclosporiasis, the intestinal illness caused by the cyclospora parasite, can take a few weeks to surface in an infected person, Dr. Sellick says. “Cyclospora needs a couple of weeks to go through a molting phase before it becomes an infectious organism,” he says. “By the time you come in with diarrhea, it could be from something you ate two weeks ago.”

That means cases being confirmed now could be linked to foods eaten quite a while ago. “Many of the newly added cases may have become ill before the lettuce was recalled on July 17, or up to two weeks after the recall due to a period of incubation, and are only now being interviewed, confirmed, and linked to the outbreak,” says Zoe Weiss, MD, the director of clinical microbiology at Tufts Medical Center in Boston.

Dr. Weiss says it can take up to six weeks to determine whether an illness belongs in this outbreak, which can further delay the data.

Cyclospora is also not always included on routine stool tests, and many people may wait to see if they have a short-lived digestive illness before visiting a doctor, says Hannah Newman, MPH, the senior director of infection prevention at Northwell’s Lenox Hill Hospital in New York City. “That means official case counts may understate the scope of the outbreak at any given moment,” she says.

There can also be delays in case reporting, even when testing confirms cyclosporiasis. “Health departments have limited resources, and that’s compounded by the gutting of the CDC that we’ve had in the past two years,” Sellick says. “If somebody has a stool sample that’s positive, local and state health departments will be alerted. Depending on the volume of cases, they’re going to try to investigate it, but that takes time.”

Symptoms of Cyclosporiasis

• Frequent, explosive, watery diarrhea
• Stomach cramps
• Nausea
• Bloating
• Fatigue

Sellick says that cyclosporiasis is “the parasitic equivalent of norovirus,” adding that the diarrhea is “terrible.”

Symptoms can improve and then return, Weiss says. If the illness goes untreated, symptoms may last for weeks. “Direct person-to-person transmission is unlikely because the parasite must spend time in the environment before it becomes infectious,” she adds.

Is There Still a Risk of Getting Sick?

People may still be at risk during this outbreak, Newman says. “The outbreak has been linked to iceberg lettuce sourced from central Mexico and recalled by Taylor Farms, and that recall should reduce the risk going forward,” she says. “However, the investigation is still active, and the U.S. Food and Drug Administration has said additional restaurants, retailers, or distribution channels could still be identified.”

The risk posed by iceberg lettuce available in stores now should be declining, Weiss says. “People should avoid any recalled iceberg lettuce, but they do not need to avoid all iceberg lettuce indefinitely,” she says. “Because other clusters may have separate sources, avoiding iceberg lettuce alone would not eliminate all current cyclospora risk.”

Other produce has been tied to previous cyclopsoriasis outbreaks, Weiss says, including:

• Leafy greens
• Salad mixes
• Fresh herbs like cilantro and basil
• Berries
• Snow peas
• Green onions

If you’re an older adult or immunosuppressed, Sellick says it’s a good idea to avoid or cook these foods to be safe.

“I wouldn't necessarily tell all people to give these foods up,” he says. “When you look at the gazillion pounds of every type of lettuce and fruit grown close to the ground that could theoretically be a risk factor, the number of cases is relatively small.”

How to Lower Your Risk of Illness

Newman encourages people to “be realistic” when navigating the outbreak. “Risk is hard to eliminate completely, but there are still sensible ways to mitigate it,” she says.

Instead of avoiding all produce, experts suggest following recall notices carefully and using routine food-safety precautions. Those include:

• Rinse produce thoroughly under running water. “Washing can reduce contamination, but it may not completely remove cyclospora from leafy greens and herbs,” Newman says.
• Consider locally grown produce. If you live in an area reporting a high number of cases and have access to a farmers market, Newman suggests shopping for your produce there. “Choosing locally grown produce may be a safer option because it is less likely to come from the supply chains currently under investigation,” she says.
• Buy whole heads of lettuce. “Rather than bagged lettuce, get a whole head of lettuce, rip off the outer leaves, toss them, and rinse the stuff inside well,” Sellick says. “It won’t make lettuce entirely safe, but it does reduce your risk.”

If you develop symptoms of cyclosporiasis that don’t go away after a few days, Weiss says you should contact a healthcare provider and mention that you may have been exposed to cyclospora. “This requires specialized testing,” she says.