Cyclospora outbreak: Taco Bell under probe in multiple US states as Michigan links cases to salad greens

Cyclospora outbreak: A dangerous parasite that has caused severe diarrhoea in Michigan and more than 31 US states may be spreading through contaminated lettuce or salad greens in Michigan, the state's Department of Health and Human Services told Bloomberg, adding that transmission from other sources cannot be ruled out.

According to The Washington Post, health officials are investigating whether Taco Bell could be linked to Cyclospora outbreaks in other states. The report said several Taco Bell outlets in the Detroit area displayed notices saying they were “currently unable to sell Lettuce, Cilantro Onion, Pico de Gallo, and Guacamole due to a nationwide recall.”

Michigan, which has recorded the highest number of cases, reported 2,640 cases of cyclosporiasis as of 13 July. The state saw a 69 per cent increase in cases compared with those reported on Friday, marking the highest number of cases ever reported in a single year.

The illness is caused by the microscopic Cyclospora parasite, which infects the intestines. It can cause nausea, stomach cramps and severe diarrhoea that may continue for several weeks.

Michigan is currently reporting the highest number of Cyclospora infections in the US. However, the US Centers for Disease Control and Prevention (CDC) said several other states, including New York, Ohio, Illinois, Indiana and Kentucky, are also recording more cases than usual.

According to the CDC's latest data, at least 843 confirmed cases have been reported across 31 states, with 86 people hospitalised, The New York Times reported.

How can people reduce the risk of Cyclospora infection?

Public health officials advise people to buy whole heads of lettuce instead of pre-washed or bagged varieties. They recommend removing the outer leaves and washing the inner leaves thoroughly under running water before eating them.

For leafy vegetables that can be cooked, experts say heating them to at least 70°C (158°F) is the safest option, as washing and chemical disinfectants may not completely remove the Cyclospora parasite.

Health officials also recommend washing all fresh fruit and vegetables under running water. However, experts warn that rinsing alone may not fully eliminate Cyclospora because the parasite can cling to the surface of produce.

Which foods have been linked to past outbreaks?

Previous Cyclospora outbreaks have often been linked to fresh produce such as basil, coriander (cilantro), lettuce and raspberries. Some infections have also been associated with travel outside the United States.

“Although we do not have a definite product identified as the source of the outbreak, we want to let Michiganders know what we have learned so far so they can take steps to protect their families,” Natasha Bagdasarian, Michigan’s chief medical executive, said in a statement.

“Early information has shown lettuce as a common product that regularly comes up during the investigation. We will continue to provide updates as we learn more.”

How to protect yourself from cyclospora

Health experts say cooking food, where possible, is the most effective way to kill the parasite.

Anyone with persistent watery diarrhoea, signs of dehydration or symptoms lasting several days should seek medical attention. Older adults, young children and people with weakened immune systems are especially advised to consult a doctor if they develop symptoms.

According to Fox Weather's food safety guidance, people should avoid buying pre-cut salad kits and chopped vegetables. Instead, they should choose whole heads of lettuce or fresh herbs.

Experts also advise removing and throwing away the outer two or three leaves of leafy greens before preparing or eating them. Fresh berries, coriander (cilantro) and basil should be washed thoroughly under clean running tap water, as simply soaking them in a bowl may not remove the Cyclospora parasite.