We are independent & ad-supported. We may earn a commission for purchases made through our links.
Advertiser Disclosure
Our website is an independent, advertising-supported platform. We provide our content free of charge to our readers, and to keep it that way, we rely on revenue generated through advertisements and affiliate partnerships. This means that when you click on certain links on our site and make a purchase, we may earn a commission. Learn more.
How We Make Money
We sustain our operations through affiliate commissions and advertising. If you click on an affiliate link and make a purchase, we may receive a commission from the merchant at no additional cost to you. We also display advertisements on our website, which help generate revenue to support our work and keep our content free for readers. Our editorial team operates independently of our advertising and affiliate partnerships to ensure that our content remains unbiased and focused on providing you with the best information and recommendations based on thorough research and honest evaluations. To remain transparent, we’ve provided a list of our current affiliate partners here.

Our Promise to you

Founded in 2002, our company has been a trusted resource for readers seeking informative and engaging content. Our dedication to quality remains unwavering—and will never change. We follow a strict editorial policy, ensuring that our content is authored by highly qualified professionals and edited by subject matter experts. This guarantees that everything we publish is objective, accurate, and trustworthy.

Over the years, we've refined our approach to cover a wide range of topics, providing readers with reliable and practical advice to enhance their knowledge and skills. That's why millions of readers turn to us each year. Join us in celebrating the joy of learning, guided by standards you can trust.

What are the Different Types of Intestinal Parasites?

Mary McMahon
Updated: Feb 05, 2024

There are two main groups of intestinal parasites: helminths and protozoa. Collectively, these organisms cause millions of infections around the world every year, in regions which vary from the urban United States to the remote areas of Africa. Left untreated, intestinal parasites can cause long term health problems or even death in the patient, and the patient can also act as a carrier to spread the parasites to other members of the community.

Intestinal parasites can be ingested in a variety of ways, with one of the leading modes of transmission being fecal to oral contact due to poor hygiene. Infections can also occur when parasites colonize water or soil, or in the case of zoonotic parasites which infect animals consumed by humans. In all cases, the parasites feed off the body to the detriment of the patient, interfering with nutrient absorption and causing a variety of symptoms.

People may develop symptoms right away, or they may be infected for years without being aware of it. When symptoms do appear, abdominal pain, nausea, vomiting, diarrhea, and cramping are all very common. The presence of intestinal parasites can be diagnosed with the use of a fecal sample which is examined for traces of organisms which could be causing infection. Patients should be aware that sometimes a sample may yield false negative or inconclusive results, necessitating another sample.

Helminths or worms are multi-celled organisms which are typically found in undercooked food, although it is also possible to be infected via contaminated water or soil. Tapeworms, roundworms, and pinworms are among the most famous and widespread. One of the classic signs of infection with worms is the presence of worms or segments in the feces.

Protozoa such as amoebas, giardia, and cryptosporidium are one celled organisms which can multiply freely in the intestinal tract. It can sometimes be difficult to identify protozoa because they are so small and difficult to identify in the feces. People who have traveled recently should alert their doctors to this fact when they request medical attention for symptoms which suggest infection with intestinal parasites, as travel is a major risk factor for infection.

Several medications can be used to eliminate intestinal parasites from the body. These drugs are generally available by prescription only to encourage patients to go to the doctor for a diagnosis so that the correct medication can be selected to eliminate the particular species causing the infection. Some patients also have success with herbal and other alternative therapies.

WiseGeek is dedicated to providing accurate and trustworthy information. We carefully select reputable sources and employ a rigorous fact-checking process to maintain the highest standards. To learn more about our commitment to accuracy, read our editorial process.
Mary McMahon
By Mary McMahon

Ever since she began contributing to the site several years ago, Mary has embraced the exciting challenge of being a WiseGeek researcher and writer. Mary has a liberal arts degree from Goddard College and spends her free time reading, cooking, and exploring the great outdoors.

Discussion Comments
By lluviaporos — On Jul 15, 2011

Intestinal parasites and malaria are two of the major reasons it is so difficult for developing countries to get on their feet.

When you think about how many people are suffering from these illnesses, which cause weakness and slow people down even in their mild forms, it's a wonder any work can get done at all.

That's one of the reasons major charities like the Bill Gates foundation and others are trying to start targeting diseases like this and completely eliminate them.

It's not just the human suffering, although that is a good enough reason.

It's also that intestine parasites contribute to economic poverty for the whole region.

By KoiwiGal — On Jul 14, 2011

When I was traveling in Africa I had a friend with me who we were sure had amoebas. She had all the awful intestinal parasite symptoms, in extreme form.

She would be constipated for three weeks, then suddenly spend a week without leaving the toilet. It was really terrible for her and she felt sick. We got her tested three times and each time she came back negative. She started worrying that it was some kind of psychosomatic thing. And the doctors refused to put her on medication.

But then she got tested a fourth time.

She came back to the hotel waving the test results and was almost jumping up and down crowing "I have amoebas!"

Finally they could put her on medication and she quickly got better.

So, yeah, if you feel sick, don't be afraid to keep getting tested, because those suckers don't always show up when you need them to.

Mary McMahon
Mary McMahon

Ever since she began contributing to the site several years ago, Mary has embraced the exciting challenge of being a...

Learn more
WiseGeek, in your inbox

Our latest articles, guides, and more, delivered daily.

WiseGeek, in your inbox

Our latest articles, guides, and more, delivered daily.