Key Takeaways
- Cyclosporiasis is a foodborne infection caused by a parasite that mainly leads to watery, explosive diarrhea.
- Cyclosporiasis doesn’t spread from person to person and is less severe than norovirus.
- Washing your hands and washing your food before you prepare it can help to prevent food-related illnesses, including cyclosporiasis.
A parasite outbreak is believed to be responsible for a food poisoning GI illness causing explosive watery diarrhea in hundreds of people across the U.S. this summer, according to the CDC. This includes more than 100 cases in New York.
Cyclosporiasis is an intestinal sickness caused by a parasite called cyclospora. The illness typically spreads during the summer when people are eating or drinking things that have cyclospora on or in them.
On average, there are approximately 500 cases of cyclosporiasis each year, according to recent CDC data.
We asked Maryrose Laguio-Vila, MD, an infectious disease specialist with Rochester Regional Health, to explain how the parasite infects people, the symptoms that follow, and how to avoid getting sick from cyclospora and other similar parasites.
How does someone get sick from cyclospora?
Cyclosporiasis does not spread from person to person.
The parasite is spread through food or water that has been contaminated with human feces - for example, produce grown in or washed with water exposed to sewage or human waste. Once the parasite is shed in the stool from an infected person, it needs several days to weeks before it can be infectious. Because of this, direct transmission from person to person does not occur.
Most people become sick within one week of eating or drinking contaminated food or drinks, but it can also happen anywhere from two days to two weeks after coming into contact with cyclospora.
According to CDC data, past cyclosporiasis outbreaks have been linked to fresh produce.
Symptoms of cyclosporiasis
Some people who become infected experience symptoms, while others may not.
The most common symptom is frequent (5-6 times a day), often explosive, watery diarrhea. Other symptoms may include:
- loss of appetite
- weight loss
- abdominal bloating/cramping
- nausea
- prolonged fatigue
- gas
Vomiting, low-grade fever, and body aches may happen less frequently.
“Because the diarrhea from cyclosoriasis is milder and comes and goes over days to weeks, people may feel like they are getting better and not realize that they need to keep drinking fluids. Over time, this can lead to dehydration,” Dr. Laguio-Vila said.
Norovirus vs. cyclosporiasis
Both norovirus and cyclosporiasis have GI symptoms like diarrhea, nausea, and vomiting. However, they are different in several important ways.
Norovirus is caused by a virus that spreads from person to person, has symptoms develop more quickly, and leads to a more severe infection with severe symptoms that last about 1-2 days.
“There are studies where one person has norovirus in their household and other people living in that household will definitely become sick with norovirus,” Dr. Laguio-Vila said.
Cyclosporiasis is caused by a parasite and does not spread from person to person; it spreads through contaminated food or drinks. Symptoms take longer to show up and are not as severe as norovirus.
Diagnosing and treating cyclosporiasis
People who become sickened by this parasite will usually have it diagnosed through a stool specimen. This is not something that is typically done unless requested specifically by a primary care or urgent care provider.
Symptoms of cyclosporiasis can be treated mostly by staying hydrated so the body does not become dehydrated and weak after losing fluids through diarrhea.
“Hydration is important – especially in hot weather,” Dr. Laguio-Vila said. “If someone is having diarrhea or nausea and vomiting, they need to stay hydrated so they can stay healthy.”
Most people will recover without any prescription medication or other treatments.
If a provider chooses to test for cyclosporiasis and the result is positive, they will prescribe an antibiotic medication called TMP-SMX (trimethoprim-sulfamethoxazole), which is also called Bactrim.
How to avoid the ‘explosive diarrhea parasite’ outbreak
Preventing sicknesses related to food starts with good hand hygiene.
Always wash your hands with warm water and foaming hand soap for at least 20 seconds – especially when you are preparing food or about to eat.
Wash your fruits and vegetables or other raw foods under running water before cutting or eating them, then store any leftover food in a refrigerator as soon as you can.
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