Acanthamoeba is a microscopic, free-living amoeba, or amoeba (single-celled living organism), that can cause rare but serious eye, skin, and central nervous system infections. The amoeba is found worldwide in the environment in water and soil. The amoeba can spread to the eyes through the use of contact lenses, cuts or wounds in the skin, or by being inhaled into the lungs. Most people will be exposed to Acanthamoeba in their lifetime, but very few will become ill from this exposure.