Isolation and Molecular Identification of Naegleria australiensis in Irrigation Water of Fuerteventura Island, Spain.

Abstract

Saline groundwater desalination has recently emerged as an alternative source of irrigation water in arid and semiarid regions due to the gradual reduction in the quantity and quality of conventional water resources for agricultural use. In Fuerteventura Island (Spain), an extremely arid territory in the European Union, brackish water desalination is one of the few available water sources for agricultural production. Very little research has been conducted on the microbiological quality of this water mainly used for irrigation of vegetable crops. Free-living amoebae (FLA) are widely distributed protozoa in the environment and have been isolated from many environmental sources such as dust, soil and water. Among the pathogenic genera included in this group, Acanthamoeba spp., Naegleria fowleri and Balamuthia mandrillaris have been reported to be causative agents of lethal encephalitis, disseminated infections and keratitis. Particularly, Naegleria fowleri is a pathogenic FLA species which causes primary amoebic meningoencephalitis (PAM). In the present study, the presence of pathogenic FLA strains on desalinated brackish water samples for irrigation has been evaluated during 7months. From the analysed samples, only one was positive for Naegleria australiensis. This is the first report of Naegleria spp. in desalinated brackish water for irrigation in Spain.