Archive · 28 Jul 2026
Cyclosporiasis Outbreak Sickens Over 4,100 in US
Cyclosporiasis is a disease caused by a tiny parasite called Cyclospora cayetanensis.
It makes people sick by infecting the cells in their intestines.
The immune system fights the parasite, but how well it does this depends on the person.
Some people get very sick with bad diarrhea, while others might not feel as bad.
Kids, older adults, and people with weak immune systems are more likely to get very sick.
The parasite is often found in contaminated food or water, especially produce from Mexico.
Doctors can test poop samples to find out if someone has it and treat it with antibiotics.
It's important to get help early if you think you have it, especially if you're in a high-risk group.
Cyclosporiasis outbreak in the U.S. has sickened over 4,100 people as of July 2026.
Major cluster of illness traced to contaminated produce imported from Mexico.
Symptoms include explosive diarrhea, loss of appetite, flatulence, cramps, nausea, fatigue, body aches, and fever.
Severity of infection depends on the immune system's response, with high-risk groups including young children, older adults, and people with weakened immune systems.
Treatment involves antibiotics usually taken for 7-10 days.
- Who
- Over 4,100 people in the U.S. as of July 2026
- What
- Cyclosporiasis outbreak caused by the Cyclospora cayetanensis parasite
- When
- 2026 outbreak
- Where
- United States, traced to contaminated produce imported from Mexico
- Why
- The immune system's response to the parasite varies, leading to different severities of illness
Immune System Response
Parasite Characteristics
Severity of Infection
Immune System Response
The severity and duration of infection depend largely on how well the immune system controls it.
Parasite Characteristics
The parasite infects the cells lining the small intestine and lives inside them, causing symptoms like explosive diarrhea.
Risk Groups
Immune System Response
Young children, older adults, and people with weakened immune systems are at higher risk of severe infection due to their immune system's inability to effectively fight the parasite.
Parasite Characteristics
The parasite has a typical incubation period of approximately one week before symptoms begin showing.
- Cause
- Cyclospora cayetanensis parasite
- Symptoms
- Explosive diarrhea, loss of appetite, flatulence, cramps, nausea, fatigue, body aches, fever
- Incubation Period
- Approximately one week
- Treatment
- Antibiotic usually taken for 7-10 days
- High-Risk Groups
- Young children, older adults, people with weakened immune systems