white roundworm parasite

worm human roundworm parasitic intestinal ascariasis nematode disease female animal health dog wildlife invertebrate isolated zoology nature ascaris white background lumbricoides medical science ugly endoparasite tapeworm hygiene infectious sanitation diarrhea helminth malnutrition anatomy scary biology education small digestive babyworm childworm fecal healthcare bowel cat abdominal blood microbiology microscope slide parasite