Human parasite

Human parasites are divided into endoparasites, which cause infection inside the body, and ectoparasites, which cause infection superficially within the skin. Parasites in general are hosts-dependent organisms that obtain nutrients while potentially harming their host in the process.

Parasitic infections cause global health concerns because they impact billions of people throughout the world at different disease severity. These infections split into the three main categories of protozoa and helminths (parasitic worms) alongside ectoparasites. Over 30% of global human population is affected by the roundworm "Ascaris lumbricoides". The incidence of certain parasitic diseases including malaria and schistosomiasis continue to rise year after year. The AIDS epidemic has worsened the situation by causing elevated rates of parasitic opportunistic infections to affect mainly weak-immune people through conditions such as cryptosporidiosis, Pneumocystis pneumonia and strongyloidiasis. Refugees and infected people moving between high-prevalence regions cause an increase in parasitic diseases to appear in places that were previously free from these infections. Public health system must develop improved strategies, as parasitic diseases continue to pose a persistent challenge to global health.

The cysts and eggs of endoparasites may be found in feces, which aids in the detection of the parasite in the human host while also providing the means for the parasitic species to exit the current host and enter other hosts. Although there are a number of ways in which humans can contract parasitic infections, observing basic hygiene and cleanliness tips can reduce its probability. The most accurate diagnosis is by qPcr DNA antigen assay, not generally available by primary care physicians in the USA: most labs offer research only service.