This thesis examines unicellular microorganism of the genus Acanthamoeba, as well as the disease it causes - acanthamoeba keratitis. It is an eye disease, which occurs mainly in people using contact lenses. Since acanthamoeba attacks visual apparatus, several parts of the thesis are dedicated to the anatomy of said apparatus, especially to the eye ball. The symptoms, diagnostics, treatment as well as prevention of the disease are included as well. The thesis furthemore mentions individual types of contact lenses, their proper hygiene and care and most of all, the danger, that comes with improper handling - acanthamoeba keratitis. A survey, that took place among elementary school and high school students, found out, that almost none of the elementary school students wear contact lenses, whereas contact lenses are worn by approximately 15% of students at high school. Among other issues, the survey concludes, that only a small part of elementary school students prefers contact lenses to glasses, though glasses are needed by a vast majority of them. At high school level, wearing contact lenses becomes more common, for aesthetics or other reasons. Ophtalmologist is regularly visited by 35 % of interviewed students. An analysis of six different natural science and biology textbooks for the 8th grade of...