free living amoeba belonging to vanella spp. isolated from a hot spring in amol city, northern iran: a case report and literature review

background: free-living amoebae have various genera that are found in several environmental niches such as soil, freshwater, dust, seawater and hot springs. most of free-living amoebae are normally harmless to humans. however, some such as acanthamoeba and also naegleria fowleri , balamuthia manderillaris and sappinia are identified as opportunistic and pathogenic amoebae that can cause eye diseases, encephalitis and meningoencephalitis in human. vannellidae are a family of free-living amoebae and exist mainly in soil, freshwater and marine habitats. this amoeba is nonpathogenic for human but can act as a trojan horse for other pathogens such as microsporidia . the present study report the occurrence  of vannella spp. in a hotsprings of amol city. materials and methods: 22 samples were taken from hot springs of mazandaran province during our previous study. the plates were checked for the presence of vannella spp. according to the specific morphological criteria. dna extraction, pcr and sequencing was performed on the positive isolate.   results: the result showed that one plate contained fan-shaped amoebae suspected to vannella . pcr analysis and sequencing was confirmed the occurrence of vannella spp. in one sample of a hot spring of amol, northern iran. conclusion: the result confirmed the presence of vannella amoebae in the hot spring of amol city. more studies are needed to clarify the real distribution of vannella spp. in environmental niches and its pathogenic potential in iran and worldwide.