Detection of Acanthamoeba spp. in water samples collected from natural water reservoirs, sewages, and pharmaceutical factory drains using LAMP and PCR in China

Various species of amoebas belonging to the genus Acanthamoeba are widely distributed in many parts of the world. Some strains of these protozoans may exist as parasites and pose risks to human health as causative agents of serious human diseases. Currently in China there is a lack of information about the distribution of Acanthamoeba strains in the environment. Accordingly, 261 environmental water samples taken from rivers, sewage, and pharmaceutical factory drains were collected in Qinghai Province, China. The material was filtered and then analysed with both LAMP and PCR assays. Of the samples examined, Acanthamoeba DNA was found in 32 (14.68%) samples with the use of LAMP; in 13 of these samples, DNA from this amoeba was also detected using PCR. Sequencing of selected positive samples confirmed that the PCR products were fragments of the Acanthamoeba 18S rRNA gene and that isolates represent the T4 genotype, known as the most common strain related to AK cases. The results indicate that surface water, as well as water taken from sewage and pharmaceutical drains, may be a source of acanthamoebic strains potentially pathogenic for humans in China. It has been also demonstrated that LAMP assays is more sensitive than PCR and can be regarded as useful tool for screening the environment for Acanthamoeba spp.