safety of drinking water concept

acanthamoeba ameba amoeba amoebeasis amoebic brain braineaiting contaminated contamination day disease encephalitis entamoeba flagellated fowleri histolytica ill illness illustration infection infectious medical medicine meningitis meningoencephalitis microbe microorganism naegleria naegleriasis nasal pam parasite parasitic pathogen pathology primary protozoal protozoan research rinsing ritual science scientific sickness tap virus water world