Boom goes the taco!

Why is your taco, well, not a taco? In a word, cyclosporiasis. ​People become infected by consuming food or water contaminated with feces containing the parasite's oocysts (a dormant, egg-like stage). It's not spread person-to-person directly — the oocysts need time (days to weeks) in the environment to become infectious after being shed in stool, so it's usually linked to contaminated fresh produce (like berries, herbs, and leafy greens) or water, rather than direct contact with an infected person.
Symptoms

• Watery diarrhea (often frequent, sometimes explosive)
• Loss of appetite and weight loss
• Stomach cramps/bloating
• Nausea
• Fatigue
• Low-grade fever (less common)

Symptoms typically start about a week after exposure and, if untreated, can last weeks to months, sometimes with a relapsing pattern (symptoms improve then return).
Diagnosis
Requires a stool sample tested specifically for Cyclospora — it's not always caught on a standard stool exam, so doctors need to request the specific test.
Treatment
The standard treatment is a course of trimethoprim-sulfamethoxazole (TMP-SMX, e.g., Bactrim). People allergic to sulfa drugs have fewer alternative options, and treatment should be discussed with a doctor.
Prevention

• Thoroughly wash fresh produce
• Be cautious with imported fresh produce and untreated water in areas where the parasite is common
• Good hand hygiene and food handling practices, since it's often linked to food service contamination

This is relevant to food safety training contexts too — cyclosporiasis outbreaks are frequently traced to restaurants and produce supply chains, which is part of why food handler certification programs cover parasite and pathogen awareness.