safety of drinking water concept, 3d showing cysts of giardia intestinalis protozoan, the causative agent of

3d africa awareness borne bug concept conceptual contaminated contamination cyst day developing diarrhea dirty disease drink drinking enteric enteropathogenic giardia giardiasis hands healthcare hygiene hygienic illness illustration india infection intestinal intestinalis lamblia lambliosis microbe microorganism nonsafe not parasite pathogenic pathological protozoa protozoan rural safe sanitation tap to travellers unclear virus washing water waterborne world