Cyclosporiasis outbreak: How to wash produce

As cases of cyclosporiasis continue to spread across the U.S., public health agencies recommend thoroughly washing your produce to lower your risk for the foodborne parasite known to cause "explosive diarrhea."

As of Thursday, cyclosporiasis cases were confirmed or being investigated in 29 states, according to The Associated Press. Cases are surging in Michigan, where more than 1,200 people have been sickened and 40 people have been hospitalized. The outbreak is not yet considered a national health emergency. 

What is cyclosporiasis? 

The backstory:

Cyclosporiasis is a diarrheal illness caused by the parasite Cyclospora cayetanensis. Experts say it’s usually found in developing countries and is spread by food or water contaminated with feces. 

In the U.S., the parasite is typically spread through fresh produce in hot weather. It doesn’t spread from person-to-person. 

Public health officials haven’t linked the most recent outbreak to a specific type of produce grower or supplies, or a specific type of produce as a potential source of the outbreak.

The Michigan Department of Health and Human Services released a list of produce that has been tied to previous outbreaks, including: 

• Bagged salad mixes and kits (pre-cut lettuce blends with romaine, iceberg, red cabbage, carrots)
• Fresh cilantro (coriander leaves)
• Fresh basil
• Raspberries
• Snow peas
• Green onions (scallions)

How to wash produce

What you can do:

Public health agencies say you should take the following steps to wash your produce before it’s consumed, though one study found that cyclospora isn’t easily removed by washing produce because it’s "stickier" than other bacteria and parasites: 

• Wash hands with soap and water before and after handling or preparing raw fruits and vegetables.
• Wash all fruits and vegetables thoroughly under running water before eating, cutting, or cooking.
• Rinse the produce before you peel it to prevent the transfer of bacteria from the knife to the fruit or vegetable. 
• Fruits and vegetables that are labeled "prewashed" do not need to be washed again at home.
• Scrub firm fruits and vegetables, such as melons and cucumbers, with a clean produce brush.
• Cut away any damaged or bruised areas on fruits and vegetables before preparing and eating.
• Dry produce with a clean cloth or paper towel to further reduce bacteria that may be present.
• Remove the outermost leaves of a head of lettuce or cabbage.
• Wash and sanitize utensils and surfaces before and after handling food. Wash and sanitize display cases and refrigerators where fresh produce is stored.
• Wash and sanitize cutting boards, surfaces and utensils used to prepare, serve or store fresh produce.
• Refrigerate cut, peeled, or cooked fruits and vegetables as soon as possible (within two hours).

Researchers also say washing your produce with one cup of white vinegar mixed with three or four cups of water can help to remove pesticides and prevent mold, but the U.S. Centers for Disease Control and Prevention and the Food and Drug Administration recommend simply rinsing the produce under running water. 

Cyclosporiasis symptoms

Timeline:

Symptoms can appear two to 14 days after exposure and may include:

• Frequent watery diarrhea
• Loss of appetite and weight
• Abdominal cramps and bloating
• Nausea (vomiting is less common)
• Low-grade fever

For people who don’t get treatment, health experts say the illness may last for a few days to over a month. Symptoms could go away and then return one or more times.

Cyclosporiasis cases by state

Local perspective:

Researchers say the illness is hard to track for several reasons, but cases are currently being investigated in 29 states. Here’s a look at cases in each state, based on the data available as of July 9: