Amoebiasis is a parasitosis caused by free-living amoebae that are able to survive in an autonomous state in all natural environments. Some species, belonging principally to the Acanthamoeba and Naegleria genera are able to parasitize humans. However, infection is rare and the estimated prevalence in Europe is between 0 and 3.5/100 000. In immunocompetent individuals, the Naegleria fowleri species is responsible for meningoencephalitis, the evolution of which is rapidly fatal. Contamination occurs though bathing in warm fresh waters. Treatment relies on administration of amphotericin B. The Acanthamoeba genus, which encompasses about 20 species, leads to potentially severe ocular disease (keratitis) in immunocompetent individuals infected through the use of contaminated contact lenses or through trauma. In immunosuppressed individuals, contamination leads to chronic disease, granulomatous encephalitis (also reported in association with species of the Balamuthia genus) and other problems including cardiac, cutaneous and pulmonary manifestations, all of which influence the prognosis. Prophylactic measures include chlorination of bathing water and swimming pools and rigorous hygiene for those using contact lenses.
Last update: December 2006