Protozoan and helminthic diseases are difficult to treat because

Protozoan and Helminthic Diseases

Explanation:

Their functionally similar and cell structure to human cells.Protozoa caused Most protist diseases in humans . Protozoa make people wiped out when they become human parasites. Chagas malady and sleeping sickness disease caused by Trypanosoma protozoa. The  giardiasis, and Plasmodium protozoa cause malaria by the Giardia protozoa.Many of the most common and destructive human ailments are brought about by a protozoan infection.   Any macroparasitic sickness of people and different creatures in which a piece of the body is tainted with parasitic worms, known as helminths.Schistosomiasis and Soil-transmitted helminthiasis are the most significant helminthiases, and are among the disregarded tropical sicknesses.