Investigation on Toxoplasma gondii by polymerase chain reaction and loop-mediated isothermal amplification in water samples from Giresun, Turkey

Abstract

Toxoplasmosis is generally asymptomatic in immunocompetent subjects, however serious manifestations of the disease may develop in immunocompromised patients and in pregnant women. The mean Toxoplasma gondii seroprevalence which is approximately 40% in Turkish population, indicates the high risk for the development of acute toxoplasmosis in those cases. One of the transmission ways of T.gondii is the consumption of contaminated water. The aim of this study was to detect the presence of T.gondii in the environmental and drinking water samples by using standard polymerase chain reaction (PCR) and loop-mediated isothermal amplification (LAMP) methods. A total of 96 water samples, of them 76 were environmental water samples collected from creeks in Giresun province center and its various districts (Piraziz, Bulancak, Keşap, Espiye) and 20 from drinking water samples, were included in the study. The samples were precipitated by the aluminium sulfate method and DNAs were isolated from the pellets formed with the sucrose gradient method. PCR and LAMP were applied to the isolated DNAs, by the use of primers F3 and B3 specific to B1 gene of the parasite. In our study, T.gondii was detected in none of the drinking water samples by PCR and LAMP, however T.gondii DNAs were positive in 13.2% (10/76) of the environmental water samples. Both of the methods yielded the same results in those samples. The stations that were positive for T.gondii were Aksu creek in Giresun province center; Gelivera creek in Espiye; Yolağzı, Keşap, Keşap Login Bridge creeks in Keşap; Bulancak, Karadere and İncivez creeks in Bulancak; Piraziz and Çayırağzı creeks in Piraziz counties. Resistance of T.gondii to chlorination and the inadequacy of the filtration processes, create a serious threat among people in contact with rivers, sea and drinking waters particularly in areas with high humidity. As far as the national literature was considered, no report about the water-borne T.gondii infections were detected in Giresun province of Black Sea region, Turkey. Thus this study will aid to the literature related to water-borne T.gondii infections. The results of this study emphasizes the essential need for appropriate disinfection procedures and purification processes before the discharge of waste water to prevent the cases of water-borne toxoplasmosis.