amoebiasis due to free-living amoebae
Free-living amebae belonging to the genera Acanthamoeba, Balamuthia, Naegleria and Sappinia are important causes of disease in humans and animals. Naegleria fowleri produces an acute, and usually lethal, central nervous system (CNS) disease called primary amebic meningoencephalitis (PAM). Acanthamoeba spp. and Balamuthia mandrillaris are opportunistic free-living amebae capable of causing granulomatous amebic encephalitis (GAE) in individuals with compromised immune systems. Sappinia pedata has been implicated in a case of amebic encephalitis. Naegleria fowleri and Acanthamoeba spp., are commonly found in lakes, swimming pools, tap water, and heating and air conditioning units.