Incidence and molecular diversity of Acanthamoeba species isolated from public baths in Hungary

Hungary has a large number of thermal baths and spa facilities which attract hundreds of thousands of tourists annually. Until recently, however, the free-living amoebae were not of public health concern. Genotyping of Acanthamoeba species, potential agents of keratitis and granulomatous encephalitis, was carried out in 20 Hungarian public baths for the first time to assess the incidence and molecular diversity of the genus in the country. Our results show that 6.7% of the samples were positive for Acanthamoeba. Of these positive samples, 6.5 and 7% was from sterilized and unsterilized pools, respectively. The 18S rRNA gene investigation of the nine Acanthamoeba strains found reveals that seven belong to the hazardous T4 genotype. The remaining two samples were of the T15 type. All the strains kept growing at 36 °C. Our results underline the need to develop a control system for free-living amoebae and supervise the disinfection of Hungarian public baths.