By: Heather Williams

While some illnesses are fairly common and highly contagious or communicable, others are a little rarer – particularly in the United States.  Cyclospora is one of those rare pathogens.  In fact, some years have absolutely no cases reported, while others linked to foodborne outbreaks have a far more significant number of cases reported.

 Cyclospora cayetanensis is a single-celled parasite, often foodborne, that causes the intestinal infection known as cyclosporiasis.  This is a well-known illness that while rare, does occur in the United States.  Cyclospora is also known to be endemic to other less developed countries around the world.  Many of the cases in the United States come from those who have traveled internationally and have returned to the United States sick.

Rates of cyclosporiasis have increased dramatically this year compared to previous years.  Los Angeles County has noticed a significant uptick in cases of cyclosporiasis.  This has health officials in that county paying attention.  But Los Angeles County is not the only location of concern with this dramatic increase in cases.

Cyclospora Statistics

Incidence of Cyclospora infection is at a drastic increase for the year 2017 compared to previous years cases.  As of September 13, 2017, 988 laboratory confirmed cases of cyclosporiasis have been reported to the Center for Disease Control.  This is significantly more than the previous highest recorded case count in 2005 of 692 reported cases.  The majority of the cases that year (582) were attributed to an outbreak related to basil imported from Brazil.  While 988 may not sound significant, consider statistics from a 15-year study on Cyclospora cases reported to the CDC.  Between the years 2000 and 2015 there were a total of 1,652 cases of cyclosporiasis.  That is 60% of the entire cases over a 15-year period in a span of just 9 months.  Something is definitely going on here.

What makes these cases interesting is that over half of those who were interviewed did not report any international travel and became ill on or after May 1, 2017.  Many times people contract the illness while traveling abroad and then return with symptoms and seek treatment at home in the United States.  While the number of states included in this years’ statistics include 40 states, of those whose infections were not attributed to international travel come from 36 states.  This seems to be a widespread problem with very little information available.

Texas leads with 163 cases so far, followed by Florida with 68. North Carolina and New York State are tied with 45 cases each, and 30 of New York’s cases coming from New York City.  Connecticut has had 23 cases, New Jersey has had 19 cases, followed by Illinois and Ohio with 17 and 16 cases respectively.  The case counts drop with Iowa having 14 cases and Massachusetts and Missouri having 13 cases each.  Maryland has had 12 cases so far and Minnesota 11.  Georgia and California have had 10 cases and Wisconsin has had 9.  Louisiana, South Carolina, and Virginia have each reported 7 cases of cyclospriasis.  Colorado has reported 6 cases, followed by Nebraska with 5 and New Hampshire, Indiana, and South Dakota having 4 cases each.  Tennessee and Michigan have 3 reported cases so far and Rhode Island, Pennsylvania, Montana, Kansas, and West Virginia have reported 2 cases each.  Trailing with 1 case reported per state is Arizona, New Mexico, Mississippi, Utah, and Washington.

At this time, no specific source has been identified.  Investigations to identify a potential source for the infection are ongoing.  As a result, it is too early to determine if the cases of Cyclospora infections in different states are related to each other or perhaps a common food item.

Previous outbreaks have been linked to basil, cilantro, lettuce, raspberries, and snow peas.  At this time the CDC does not have a recommendation to avoid any particular food and no produce item linked to Cyclospora infection has been issued for recall.  “Consumers should continue to enjoy the health benefits of eating fresh fruits and vegetables as part of a well-balanced diet.”

Los Angeles County Health Advisory

While many states and counties are affected by this infection, Los Angeles County does not usually have many cases of Cyclospora infection.  The recent increase has prompted local health authorities to heed the Health Advisory following the CDC Health Advisory issued on August 7, 2017.

A message to primary care, emergency medicine, urgent care, gastroenterology, and infection disease providers at all clinical and reference laboratory levels were given notice on the increase of Cyclospora cayetanensis infections being reported nationwide.

Los Angeles County had 14 Cyclospora cases between June 1, 2017 and August 1, 2017.  There were no cases earlier in the year and only 7 cases were reported in 2016.  While 14 cases do not seem like a high number compared to the cases in Texas and Florida, it is significantly higher for this particular county.

The County health department is urging healthcare providers to consider testing for cyclosporiasis for cases involving prolonged or relapsing diarrheal disease.  This is particularly important because many routine screen panels do not include Cyclospora, so a specific test request may be required.

Prevention Measures

Not all exposures can be avoided.  For example, swimming in potentially contaminated waters is a high exposure risk.  While you may be envisioning avoiding green, murky, smelly water (those should of course be avoided for many reasons), sometimes the most unexpected source could create a contamination event.  A community pool, even though it should be fairly highly chlorinated, is not a safe water source.  Oftentimes, the amount of chlorine in the water is not sufficient to kill the parasite.  This allows a potential risk for spread of the disease if an infected person accidently defecates in the pool.  While the mess may be cleaned up, the microscopic infectious cells remain.

There are, however, a few things that you can do to control exposure.  Aside from avoiding public pools, you can take your health into your own hands by how you handle the fruits and vegetables that you eat.  Washing fruits in vegetables with a brush and water can reduce the risk of cyclosporiasis. Additional care with handwashing before and after handling food and always washing hands after using the bathroom can reduce risk of spreading infection.  While the parasite cannot be passed from person to person immediately, infected feces (even in small amounts) can be highly contagious.

 

 

Sources:

 https://www.cdc.gov/parasites/cyclosporiasis/outbreaks/2017/index.html

 https://www.cdc.gov/parasites/cyclosporiasis/outbreaks/foodborneoutbreaks.html

 http://www.latimes.com/local/california/la-me-ln-cyclospora-20170810-story.html

 http://publichealth.lacounty.gov/eprp/Health%20Alerts/Cyclospora%20CDC%20Advisory%208.9.2017.pdf