Taco Bell under investigation as diarrhoea-causing parasite cyclosporiasis outbreak grows

A popular food chain is under investigation over claims it may be linked to the rapid spread of a parasite which can cause “explosive” diarrhoea.

While the cause of the major outbreak — now estimated to be impacting more than 7000 people — is unknown, investigators are looking at Taco Bell as a potential source, the Washington Post reported.

Since May 1, the Centre for Disease Control and Prevention in the US has recorded 1645 confirmed cases and a further 5100 are under investigation.

An additional 440 cases were contracted outside of the US.

The state of Michigan has been the hardest hit by the outbreak, with hundreds of cases reported each day.

Based on interviews with more than 1000 patients, investigators believe lettuce could be the culprit.

“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 published by the Washington Post.

“Early information has shown lettuce as a common product that regularly comes up during the investigation.”

While some of those had eaten at Taco Bell before getting sick, not all had.

As of July 13, 141 people had been hospitalised with the parasite and cases had been reported across 34 states.

Investigators believe the actual number of cases could be much higher.

“We assume a 6-week reporting lag between illness onset and case reporting to CDC; therefore, we anticipate that case counts will continue to rise as data are received,” a spokesperson said on their website.

Usually, the parasite is contracted by consuming water or food contaminated by faeces.

As investigators race to determine the cause of the spike in infections, some locations of Taco Bell in Michigan have put up signs saying that some ingredients will not be served.

“We are currently unable to sell Lettuce, Cilantro Onion, Pico de Gallo, and Guacamole due to a nationwide recall. We apologize for the inconvenience. Any items ordered that normally come with these items WILL NOT contain them,” the signs say, as reported by the New York Post.

Taco Bell said it will continue to be guided by health authorities

“The health and safety of our guests is our top priority,” the company said in a statement published by the Washington Post.

“Public health officials have not confirmed a link to Taco Bell or any specific ingredient, supplier, restaurant or retailer.

“While authorities continue their broader review, Taco Bell has voluntarily and temporarily removed limited ingredients at select restaurants as a precautionary measure.”

The Cyclospora parasite is a “nationally notifiable disease” meaning all cases must be reported to the government by health officials.

Symptoms of the parasite usually start about a week after infection and the most common side-effect is “watery diarrhoea with frequent and sometimes explosive bowel movements”, the CDC said.

Other symptoms can include nausea, loss of appetite, weight loss, cramping, bloating, and increased gas.

Vomiting, body aches, head aches, fever, and flu-like symptoms have also been reported but are more rare.

Symptoms can last anywhere between a few days and more than a month.

Sick people range between two and 95 years old and 56 per cent of those infected as of July 13.