protozao entamoeba histolytica cyte stage

analyzing animal ascariasis ascaris cestode diagnosis disease egg eggs exam fecal feces fluke helminthology helminths hookworm human hymenolepis infection laboratory lumbricoides microscope microscopy nematoda nematode paragonimiasis parasite parasitic pinworm protozoa research roundworm science stercoralis stool strongyloides taeniasis tapeworm test threadworm trichinosis trichiura trichuliasis trichuriasis trichuris viverrini westermani whipworm worm