Health officials in the United States are exploring a cyclospora outbreak as cases have been rising significantly this year.
Since May 1, the Centers for Disease Control and Prevention (CDC) has reported 1,645 domestically acquired cases and is looking into over 5,100 more to see if they connect to the outbreak.
The CDC predicts infections may continue to increase through August. Although cyclospora rarely leads to severe health issues, it can cause persistent gastrointestinal problems and is generally treated with antibiotics.
Here’s a breakdown of what’s known about cyclospora and the current outbreak:
What is cyclospora?
Cyclospora is a microscopic parasite responsible for an intestinal illness known as cyclosporiasis. Once it enters the body, it can infect the intestines, with symptoms that may last for weeks if untreated.
Unlike many other foodborne illnesses, cyclospora mostly does not spread directly from person to person. After being expelled from the body, the parasite requires days to weeks in the environment to become infectious again.
Infections from cyclospora are less common compared to those caused by bacteria like salmonella or E. coli. However, outbreaks in the U.S. have been occurring more frequently in the last decade—a trend likely influenced by improved testing and favorable environmental conditions, like warmer temperatures, that aid the parasite’s survival.
How do people get infected with cyclospora?
The CDC indicates that individuals typically get infected after consuming food or drinking water tainted with the parasite, often due to human waste contamination.
Fresh produce—especially leafy greens, herbs, and berries—has been implicated in previous outbreaks, mainly because they are usually consumed raw and may have been washed with contaminated water.
Currently, health officials have not pinpointed the source of the outbreak in the U.S. The FDA is tracing various fresh produce items through the supply chain to identify where the contamination originated.
They’re looking into lettuce that Michigan health officials suspect could be a source, but there’s no confirmation yet regarding specific items, growers, or suppliers involved.
The investigation involves interviewing infected individuals about their recent meals and tracking those foods back to their distributors, sometimes all the way to the farm.
What foods are commonly linked to cyclospora?
Cyclospora infections have typically been traced to raw fruits and vegetables in past outbreaks. Foods identified include lettuce, bagged salads, cilantro, basil, raspberries, snap peas, coleslaw, vegetable trays, and fresh fruit mixes.
Taco Bell has reportedly taken precautions by removing lettuce, cilantro, pico de gallo, and guacamole from some menus during the investigation.
Experts also suggest exercising caution when handling fresh produce. Rinsing fruits and vegetables thoroughly—even if marked as “pre-washed”—can minimize contamination risks.
What are the symptoms of a cyclospora infection?
Generally, symptoms of a cyclospora infection start about a week after consuming contaminated food or water, though they could manifest as early as two days or as late as two weeks post-exposure.
The primary symptom is frequent, watery diarrhea, but it can also bring about loss of appetite, weight loss, stomach cramps, bloating, gas, nausea, and extreme fatigue.
Some may experience vomiting, body aches, headaches, mild fever, or other flu-like symptoms. Interestingly, not everyone in areas with prevalent cyclospora infections show symptoms.
How can you prevent it?
Practicing good food hygiene might reduce the risk of infection, although washing produce doesn’t guarantee the removal of the parasite. Experts recommend:
- Washing hands thoroughly with soap and water before and after preparing fresh produce.
- Rinsing all fresh produce under running water prior to consumption, even items deemed “pre-washed.”
- Using a clean produce brush for firm fruits and vegetables.
- Refrigerating cut, peeled, or cooked produce within two hours to ensure safety.
Where has it spread in the United States?
According to the latest CDC data, cyclospora infections have been reported in over 30 states this year, predominantly in the Midwest and Northeast regions.
Michigan has seen the highest infection rates, with estimates ranging from 501 to 900 cases. Other states experiencing significant numbers include New York (161-300 cases), North Carolina (81-160), as well as Illinois, Indiana, Kentucky, New Jersey, and Texas each with 31-80 cases.
In addition, cases have emerged in states such as Alaska, Arizona, Arkansas, California, Colorado, and several others, although many of these have had fewer than 30 infections reported.
What’s the current situation?
Cases are notably increasing in and around southeastern Michigan, but officials have not deemed this a national health emergency just yet.
There’s no indication that the parasite has mutated to become more infectious, stated Dianna Blau from the CDC.
While thousands of cyclospora cases are reported annually in the U.S., it remains uncertain how exceptional this year will turn out to be. The current cases reported are four times higher than the same time last year, according to available CDC data, which tends to lag behind state reports.
Michigan seems to be facing severe consequences, but the state’s proactive approach in investigating and reporting cases could be influencing perceptions that this is primarily a Michigan issue, observed Natasha Bagdasarian, the state’s chief medical executive.
How long does a cyclospora infection last?
The illness could last several days to over a month without treatment.
Diarrhea might improve temporarily only to return, and fatigue can persist even after other symptoms have resolved.
How is cyclospora diagnosed?
A cyclospora infection is diagnosed through stool sample testing.
Since the parasite isn’t always present in detectable quantities, a single test might not suffice. Consequently, doctors frequently request multiple stool samples collected over different days to better capture the infection.
Laboratories utilize specialized tests for detection, including microscopic examination and molecular techniques like polymerase chain reaction (PCR) to identify cyclospora’s genetic material.
What antibiotic is used to treat cyclospora?
The standard treatment for cyclospora infection, according to the CDC, is the antibiotic trimethoprim-sulfamethoxazole (TMP-SMX), known by brand names like Bactrim and Septra.
This medicine is usually prescribed for a duration of seven to ten days, though individuals with weakened immune systems may require longer treatment.
Most healthy individuals ultimately recover without antibiotics, but without treatment, symptoms like diarrhea can linger for weeks or longer, and may return after seeming to resolve.
What should you do if you think you have cyclospora?
It’s essential to stay hydrated due to the prolonged diarrhea that comes with cyclosporiasis. Drinking water, broth, or electrolyte beverages is advisable while avoiding alcohol and caffeine that could worsen dehydration.
If appetite is low, eating small portions can help. It’s critical for anyone prescribed antibiotics to complete the entire course as instructed, even if symptoms improve before finishing the medication.
