Intestinal parasites are organisms that live in the digestive tract of humans and animals, feeding on nutrients from their host. Common types include worms, such as tapeworms and roundworms, and protozoa, like Giardia. These parasites can cause various health issues, including abdominal pain, diarrhea, and malnutrition. Transmission often occurs through contaminated food or water, poor hygiene, or close contact with infected individuals. Diagnosis typically involves stool tests, and treatment may include medications to eliminate the parasites. Preventive measures include practicing good hygiene, cooking food thoroughly, and drinking clean water.