Foodborne Parasites: How to Protect Yourself From Infection

Could a single bite of contaminated food expose you to a parasite? Yes, it is possible—but not every contaminated bite causes infection, and the risk depends on the parasite, the food, and how it was prepared.

Foodborne parasites are organisms that can enter your body through contaminated food or water. Some cause mild digestive symptoms, while others can lead to serious illness or complications.

The good news is that simple food-safety habits can greatly reduce your risk.

Foods that can carry foodborne parasites

Kitchen Cross-Contamination Prevention Guide

1. Raw or undercooked meat

Certain meats can carry parasites such as Toxoplasma gondii and Trichinella. Thorough cooking is essential.

2. Raw or undercooked fish and shellfish

Some fish and shellfish can transmit parasitic worms or flukes. Safe preparation matters, especially for freshwater fish.

3. Unwashed fruits and vegetables

Produce may become contaminated by soil, unsafe irrigation water, or animal or human waste.

4. Unsafe drinking water

Water contaminated with certain parasite cysts or eggs can transmit infection, particularly where sanitation is inadequate.

These are recognized transmission routes for several foodborne parasites.

CDC

7 practical ways to protect yourself

Cook meat thoroughly. Use a food thermometer when possible. For example, poultry should reach an internal temperature of 74°C (165°F).

Wash produce under running, safe water. Scrub firm fruits and vegetables and remove damaged areas.

Drink safe water. If the water supply is uncertain, use properly treated or boiled water.

Prevent cross-contamination. Keep raw meat separate from cooked food, salads, and other ready-to-eat items.

Wash your hands with soap. Do so before preparing food, after using the toilet, and after handling raw meat or soil.

Choose reputable food vendors. Pay attention to food hygiene, refrigeration, and thorough cooking.

Be especially cautious during pregnancy or with a weakened immune system. Certain parasitic infections can have more serious consequences in these circumstances.

These precautions are supported by CDC food-safety guidance.

CDC

What symptoms should you watch for?

Symptoms vary by parasite, and some infections cause no obvious symptoms at first. Possible signs include:

Abdominal pain, diarrhea, nausea, or vomiting.

Unexplained fever or fatigue.

Muscle aches or swelling around the eyes after certain undercooked-meat exposures.

Persistent digestive problems or unexplained weight loss.

Seek medical advice if symptoms develop after a suspected exposure. Severe abdominal pain, bloody diarrhea, dehydration, neurological symptoms, or high fever warrant prompt medical evaluation. If you are pregnant or immunocompromised and suspect a significant exposure, contact your healthcare professional even if you feel well.

Do not take deworming medicines just in case. Different parasites require different tests and treatments, and not all infections respond to the same medication.

The bottom line

One bite of contaminated food can sometimes transmit a parasite, but infection is not inevitable. You can substantially reduce your risk by cooking food properly, washing produce, drinking safe water, and maintaining good kitchen hygiene.