Three types of parasites can cause disease in humans. They are protozoa, carried by mosquitos, helminths, such as roundworm, and ectoparasites, for instance lice and bed bugs.
Parasites are organisms that live in or on a living host of another species. They survive by taking nutrients from this host.
In this article, we detail the different types of parasites and parasitic infections that can affect humans.
A note about sex and gender
Sex and gender exist on spectrums. This article will use the terms “male,” “female,” or both to refer to sex assigned at birth. Click here to learn more.
There are three types of parasites that can cause diseases in humans.
- Protozoa: Protozoa parasites are single-celled organisms. Protozoa can only multiply, or divide, within the host.
- Helminths: These are worm parasites. They are
typically visibleto the naked eye at their adult stage. Unlike protozoa, they cannot multiply in humans.
- Ectoparasites: These live on rather than in their hosts. They include lice, fleas, and mosquitos.
According to the
Many types of parasites can affect humans. Here are some examples of parasites and the diseases they can cause.
Plasmodium is a single-cell parasite that causes malaria. This disease causes fever, headaches, and chills. It can be fatal.
The Anopheles mosquito carries this bloodborne parasite and transmits it through biting humans. There are five types of plasmodium that can cause malaria, and there were an estimated
This affects the blood, muscles, nerves, heart, esophagus, and colon. It is transmitted through an insect bite. Over
This is a parasitic pneumonia
This tiny ameba
Also known as “trich,” this is a sexually transmitted infection (STI). It is the result of the parasite Trichomonas vaginalis. It affects the female urogenital tract. It can exist in males, but usually without symptoms.
Other protozoa infections include:
Worms, or helminth organisms, can affect humans and animals. Types of worm parasites include:
Beef and pork tapeworms
A roundworm transmits this infection from animals to humans. It affects the eyes, brain, and liver.
Elephantiasis lymphatic filariasis
Other types of worm parasites include:
- Echinococcus tapeworm
- Diphyllobothrium latum tapeworm
- raccoon roundworm
- Guinea worm
- Enterobiasis pinworm
- Fasciolosis liver fluke
- Fasciolopsiasis intestinal fluke
- Loa loa filariasis
- river blindness
- lung fluke
- schistosomiasis, bilharzia, or snail fever
Ringworm is sometimes mistaken for a worm, but it is not a worm. It is a fungal infection.
Ectoparasites are parasites that live on the outside of the body. Fleas, lice, and bedbugs are common ectoparasites.
Demodex folliculorum are tiny mites that live in and around the hair follicles. Typically they do not cause noticeable adverse symptoms. However, they can cause a range of ocular diseases if they infest the eyelashes or eyebrows.
Screwworms are the fly larvae that burrow into the skin. They can cause severe infection and disease.
There are three main types of parasites that can affect humans: protozoa, helminths, and ectoparasites. These parasites can live on or in the human body and cause various diseases.
These parasites are often the result of consuming contaminated foods or water, though insects and other animals can also carry parasites.