safety of drinking water concept

awareness borne bug concept conceptual contaminated contamination day developing diarrhea diarrheal dirty disease drinking enteric enteropathogenic healthcare hominis human hygiene hygienic illustration infection infectious intestinal intestinalis intestine medical medicine microbe microbes microorganism not organism parasite parasitic parasitology pathogenic pathological pentatrichomonas protozoa protozoan rural safe sanitation tap trichomonas water world