While fairly common in developing tropical, or sub-tropical countries, Cyclosporiasis – an infection usually acquired through consuming food or water contaminated with Cyclospora cayetanensis - is relatively rare in the United States.
Unlike the more common cryptosporidium, which can be easily be passed from human-to-human, Cyclospora is rarely transmitted directly from an infected host.This is because hosts infected with Cyclospora shed unsporulated (non-infective) cysts in their stool which require days or even weeks to mature into infectious agents. Infection is characterized by prolonged bouts of watery diarrhea, which may persist or reoccur over a period of weeks.
We tend to see non-travel acquired Cyclospora cases in the United States during the summer months, usually peaking in June or July.In 2013 we saw a particularly widespread event, with 631 cases reported from 25 states and New York City (link). Texas was the hardest hit (270 cases), followed by Iowa (140 cases) and Nebraska (87 cases).
This outbreak slowed, and finally ended, by the end of August.The CDC’s MMWR carried a brief post-mortem on the outbreak (link) which identified not one – but at least two separate outbreaks – and that `the food item associated with illness in Texas was different from that implicated in restaurant-associated cases in Iowa and Nebraska’.
On Monday, the Texas DSHS issued the following statement on a recent surge in Cyclospora infections in their state. Health officials there are particularly anxious to track down the source, in hopes that a repeat of 2013's outbreak can be avoided.
News ReleaseThe CDC maintains an extensive Cyclosporiasis (Cyclospora Infection) web page, where you can find additional information. There you will find additional information on outbreaks, epidemiology, and Treatment, which according to the CDC:
July 17, 2017
A spike in illnesses caused by the parasite Cyclospora in June and July is prompting the Texas Department of State Health Services to ask health care providers to be on guard for the illness, pursue testing, and report cases to their local health department. Within the past month, 68 cases have been reported in the state, and DSHS is working with local health departments to gather information about the illnesses and identify a source.
Cyclosporiasis is an intestinal illness caused by consuming food or water contaminated with the microscopic Cyclospora parasite. The main symptom is watery diarrhea lasting a few days to a few months. Additional symptoms may include loss of appetite, fatigue, weight loss, abdominal cramps, bloating, increased gas, nausea, vomiting and a low fever. Symptoms may come and go multiple times over a period of weeks or months.
People with symptoms that could be related to Cyclospora should contact their health care provider for treatment. A health advisory issued today asks providers to test patients who have diarrhea lasting more than a few days or diarrhea accompanied by severe loss of appetite or fatigue. Health care providers should promptly report cases so that public health can investigate them and attempt to determine the source in order to head off future cases.
Past outbreaks in the U.S. have been associated with consumption of imported fresh produce, including fresh pre-packaged salad mix, raspberries, basil, snow peas, and mesclun greens. Texas has had multiple outbreaks linked to cilantro.
DSHS recommends thoroughly washing all fresh produce, but that may not entirely eliminate the risk because Cyclospora can be very difficult to wash off. Cooking will kill the parasite. Infection is generally not transmitted directly from person-to-person. There were 148 cases of cyclosporiasis in Texas reported last year.
Trimethoprim/sulfamethoxazole (TMP/SMX), sold under the trade names Bactrim*, Septra*, and Cotrim*, is the usual therapy for Cyclospora infection. No highly effective alternative antibiotic regimen has been identified yet for patients who do not respond to the standard treatment or have a sulfa allergy.Under Prevention and Control, they write:
Most people who have healthy immune systems will recover without treatment. If not treated, the illness may last for a few days to a month or longer. Symptoms may seem to go away and then return one or more times (relapse). Anti-diarrheal medicine may help reduce diarrhea, but a health care provider should be consulted before such medicine is taken. People who are in poor health or who have weakened immune systems may be at higher risk for severe or prolonged illness.
On the basis of the currently available information, avoiding food or water that may have been contaminated with feces is the best way to prevent cyclosporiasis. Treatment with chlorine or iodine is unlikely to kill Cyclospora oocysts. No vaccine for cyclosporiasis is available.
The U.S. Food and Drug Administration's (FDA) Center for Food Safety and Applied Nutrition (CFSAN) publishes detailed food safety recommendations for growers and suppliers. In its Guide to Minimize Microbial Food Safety Hazards for Fresh Fruits and Vegetables, CFSAN describes good agricultural practices (GAPs) and good manufacturing practices (GMPs) for fresh fruits and vegetables. The guidelines address the growing, harvesting, sorting, packaging, and storage processes; following the guidelines can help reduce the overall risk for microbial contamination during these processes. The precise ways that food and water become contaminated with Cyclospora oocysts are not fully understood.
CDC monitors the occurrence of cyclosporiasis in the United States and helps state health departments identify and investigate cyclosporiasis outbreaks to prevent additional cases of illness.