Cyclospora outbreak investigations are notorious for being very difficult to pinpoint the vehicle and/or the source.

Cyclospora life cycle/CDC
Cyclospora life cycle/CDC

I remember talking to Iowa Dept. of Public Health (IDPH) Medical Director and State Epidemiologist, Dr. Patricia Quinlisk on the radio show during the 2013 outbreak and listened to her describe the investigation saying she was optimistic that investigators will be able to figure out the source of the outbreak, at least at a certain level. However, will they may not be able to pinpoint the exact farm where the tainted veggies came from.

In fact, the Centers for Disease Control and Prevention (CDC) says identifying the particular food item/ingredient that caused an outbreak of cyclosporiasis can be very challenging.

LISTEN: Parasites 101: Cyclospora

Sometimes the food vehicle/source is identified, sometimes not. Since 2000, about 20 cyclospora outbreak investigations came up empty concerning this information.

The current outbreak of cyclosporiasis in the US has topped 1,000 cases year-to-date (1031 to be exact) with a little more than half (578) being locally transmitted from 36 states.

As of Sept. 20, federal health officials report no specific vehicle of interest has been identified, and investigations to identify a potential source (or sources) of infection are ongoing.

Historically, previous outbreaks have been linked to various types of imported fresh produce (e.g., basil, cilantro, mesclun lettuce, raspberries, snow peas).