Arizona reports several cases in nationwide cyclosporiasis parasite outbreak

PHOENIX - A growing outbreak of cyclosporiasis is drawing attention from health officials as cases continue to rise across the country, including in Arizona.

The illness, caused by the microscopic parasite cyclospora, can lead to weeks of gastrointestinal illness.

What they're saying:

Doctors say symptoms can include loss of appetite, nausea and vomiting that may last for weeks — sometimes as long as a month — but one symptom is considered the hallmark of the infection.

"The explosive diarrhea is really hallmark," said Dr. Natasha Bhuyan of One Medical.

Health officials say dozens of states are investigating cases of cyclosporiasis, including Arizona, where 10 cases have been reported.

In Michigan, health officials have reported more than 1,500 cases and 44 hospitalizations.

The Centers for Disease Control and Prevention said states are likely reporting more cases of cyclosporiasis than are currently reflected in the agency's national data.

Since May 1, the CDC said they have received reports of 843 confirmed domestic cases and said they are aware of more than 1,500 additional cases that are awaiting further analysis and confirmation.

Dig deeper:

"We typically see this infection in the summer and that’s because more people are eating more imported fruits and vegetables around that time," Bhuyan said. "This year we’re seeing more cases of cyclosporiasis than we have before."

Unlike many foodborne illnesses commonly linked to meat, Bhuyan said cyclospora is most often associated with fresh produce, including raspberries, blackberries, basil and leafy greens.

"People look back and say, ‘I didn’t eat anything unusual yesterday or the day before,' but it might have come from fruit they ate even weeks ago," Bhuyan said.

Health experts say people become infected after eating fresh produce contaminated with the parasite, which is typically spread through human fecal contamination.

Local perspective:

University of Arizona Associate Professor Jerry Lopez, who studies cyclospora, said investigators are working to trace the source of the latest outbreak.

He said contamination can occur through multiple pathways, including water used to irrigate crops.

"From farm to fork, that time frame is really quick," Lopez said.

Lopez said the complexity of the food supply can make outbreaks difficult to trace.

"It's chopped up, goes through a wash. If it was contaminated, then it’s packaged, and then it might be packed into multiple types of things, so then you have shipments of these commodities that can definitely end up going to different regions," Lopez said.

'You have to wash your hands’

Bhuyan said another warning sign is symptoms that appear to improve before returning again. She warned that prolonged diarrhea can lead to dehydration and, in some cases, hospitalization.

She also said the parasite can be difficult to eliminate, surviving on frozen fruit and not always being removed through washing alone.

"The alcohol-based sanitizers are not effective against this parasite, so you have to wash your hands with soap and water," Bhuyan said. "Really, the only way to truly eradicate it is if you cook these foods, but they're fruits, so people don’t always eat them cooked."

Despite the increase in cases, Bhuyan said people should not stop eating fruits and vegetables.

She said the infection is treatable with antibiotics, and the health benefits of eating produce outweigh the risk.

HealthArizonaNews