The 6 Most Common Parasites that infect the Human Body

There are different types of human parasitic worms that include pinworms, tapeworms, roundworms, hookworm, flukes, whipworms, and many others. The parasites vary in size and shape, and they cause different types of problems. They consume a significant portion of nutrients from a person leaving him to her hungry and unhealthy. Below is a list of the common parasites of the human body.

1. Tapeworms

Infection by these intestinal parasites can be diagnosed by checking for ova and the parasite in stool samples. These worms exist in different genera that include Spirometra, Hymenolepis, Taenia, Dipylidium, Diphyllobothrium, and Echinococcus. Tapeworms do not have an intestinal tract, and therefore, the use integuments to take nutrient from the human body. Individuals who are infected can be treated by administering anthelmintic drugs such as albendazole, praziquantel, and niclosamide.

2. Human pinworm (Enterobius vermicularis)

These intestinal parasites affect many people in the United States. The pinworms often live in a human being’s small intestines. The female parasite moves to the anus at night and lays its eggs in the person’s perianal skin folds. The larvae then travel to the lower intestine after being hatched, and they lead to retroinfection. Most people who have been infected are asymptomatic but they may trigger appendicitis in children. The pinworm is diagnosed by checking for ova and the female pinworm in perianal swabs through a microscope. The sample needs to be taken in the morning. Anthelmintic drugs such as albendazole, mebendazole, and pyrantel pamoate can be used for treatment.

3. Ascaris

Ascariasis has been known to be the world’s most common parasitic worm infection. The Ascaris lumbricoides is a worm that grows to up to 35 centimeters long, and it is the biggest roundworm that lives in the human body. The parasite can stay in a person’s small intestines for as long two years if it is not treated. One female Ascaris lumbricoides can lay approximately 200,000 eggs in the soil, and their life cycle involves different organs that include the lungs and the liver. An infected person is asymptomatic, but in a few cases, individuals may develop malnutrition, stunted growth, hepatobiliary injury, pneumonia, and eosinophilia.

4. Hookworms (Necator americanus and Ancylostoma duodenale)

These parasites are widespread, and they infect millions of people across the world. They have been ranked second after ascariasis in the list of the most common intestinal infections. Hookworms enter the human body by their larvae penetrating through the skin when a person comes into contact with contaminated soil. The worms travel to the lungs and then migrate to the intestines during swallowing. These parasites do not multiply in the body, and therefore, the infection can end if one is not exposed again. Ancylostoma has a lifespan of 1 to 3 years while Necator lives for 3 to 10 years. Most common symptoms include vague abdominal pain, nausea, or diarrhea, and they can be treated by using anthelmintic drugs.

5. Intestinal Trematodes

These are also referred to as intestinal flukes, and they usually vary in size. The most common species of the flat hermaphroditic parasites include Echinostoma, Heterophyes heterophyes, and Metagonimus yokogawai. People are mainly infected after consuming an undercooked intermediate host, which may be vegetables, fish, or any other animal. The worms live on the wall of the patient’s small intestines. Most people are asymptomatic, but adult flukes lead to ulceration and inflammation. Patients can be treated by taking three doses of anthelmintic medication.

6. Entamoeba histolytica

This parasite is a protozoan, and it leads to a disease that is known as amebiasis. It infects the human body through ingestion of contaminated food, water, or soil. The parasites of often penetrate the mucosal barrier lead to the destruction of tissues, colitis, and bloody diarrhea. The trophozoites can move to organs such as the lungs, liver, and brains through the blood hence causing the formation of abscesses. Asymptomatic amebiasis can be cured by using paromomycin or iodoquinol while tinidazole or metronidazole can be used in treating a severe infection.

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