Humans are hosts to nearly 300 species of parasitic worms and over 70 species of protozoa, some derived from our primate ancestors and some acquired from the animals we have domesticated or come in contact with during our relatively short history on Earth.
One of the largest fields in parasitology, medical parasitology is the subject which deals with the parasites that infect humans, the diseases caused by them, clinical picture and the response generated by humans against them. It is also concerned with the various methods of their diagnosis, treatment and finally their prevention & control. A parasite is an organism that live on or within another organism called the host . These include organisms such as:
Plasmodium spp., the protozoan parasite which causes malaria. Entamoeba and Giardia, which cause intestinal infections (dysentery and diarrhoea). Multicellular organisms and worms such as Schistosoma spp., Wuchereria bancrofti, Necator americanus (hookworm) and Taenia spp. (tapeworm). Ectoparasites such as ticks, scabies and lice.
Medical parasitology can involve drug development, epidemiological studies and study of zoonoses.