CDC Warns of Increase in Cyclospora cayetanensis Infections in United States

The Centers for Disease Control and Prevention (CDC) Health Alert Network issued a health advisory this afternoon stating that it is working with the US Food and Drug Administration (FDA), as well as state and local health departments to investigate an increase in reports of cyclosporiasis.

Health care providers are advised to “consider a diagnosis of cyclosporiasis in patients with prolonged or remitting-relapsing diarrheal illness.” Because testing for cyclospora is not routinely completed in most US laboratories, health care providers must specifically order the test for the parasite, regardless of whether “testing is requested by ova and parasite (O&P) examination, by molecular methods, or by a gastrointestinal pathogen panel test.”

Cyclosporiasis is a nationally notifiable disease; health care providers should report suspect and confirmed cases of infection to public health authorities.

According to the CDC, “Cyclosporiasis is an intestinal illness caused by the parasite Cyclospora cayetanensis.” Consumption of contaminated food or water can lead to infection; however, the parasite is not transferable from one person to another.

Symptoms occur about 7 days (range: 2 days to > 2 weeks) after ingesting the parasite and include:

• Watery diarrhea (can be profuse)*
• Anorexia
• Fatigue
• Weight loss
• Nausea
• Flatulence
• Abdominal cramping
• Myalgia
• Vomiting**
• Low-grade fever**

*most common symptom

**less-common symptoms

Without treatment, an individual may remain ill for several days to a month or longer. A “remitting-relapsing course” may occur.

Treatment for cyclosporiasis is a course of trimethoprim/sulfamethoxazole (TMP/SMX). For those patients who are allergic to TMP/SMX, or who cannot tolerate the treatment, the CDC suggests observation and symptomatic care, as no effective alternate treatments have been identified.

Cyclosporiasis commonly occurs in tropical and subtropical regions; however, infections do occur in the United States. These outbreaks mostly occur during the spring and summer months and have been linked with imported fresh produce in the past, such as, basil, cilantro, mesclun lettuce, raspberries, and snow peas. According to the health advisory on the recent outbreak, “to date, no commercially frozen or canned produce has been implicated.”

A total of 206 cases of cyclosporiasis have been reported to the CDC as of August 2, 2017. This is much higher than the number of cases reported at this time last year (88). The cases reported this year became ill on or after May 1, 2017. Twenty-seven states reported infections and 18 of the 206 cases required hospitalization. Investigations to identify the source are ongoing. It is still too early to tell if they cases across the 27 states are related.

Feature Image Content Provider: CDC/ DPDx - Melanie Moser