Evaluating the Drinking Water Distribution System of Lahore for Free‐Living Amoebas, Particularly <i>Naegleria</i> spp.

Free-living amoebas are ubiquitous in distribution systems and recreational waters. Numerous studies have described the problem posed by their presence in the drinking water distribution systems of Lahore; however, very few studies have been done on <i>Naegleria</i> spp., particularly <i>Naegleria fowleri</i> that causes primary amoebic meningoencephalitis. In this study, we aimed to screen for the free-living amoebas in 100 water samples from nine zones in Lahore. These samples included water from mosques (<i>n</i> = 45), homes (<i>n</i> = 45), swimming pools (<i>n</i> = 10), and the Lahore canal. Cysts (3-4 <i>μ</i>m) and rounded trophozoites (4-5 <i>μ</i>m) along with elongated trophozoites (8-10 <i>μ</i>m) were observed to be present in 37 (82.2%) water samples from mosques. In water from homes, we detected rounded trophozoites (5 <i>μ</i>m) and elongated trophozoites (10 <i>μ</i>m) from the Lahore canal. There was also a positive association with temperature (odds ratio 20.329, 95% CL) and a trend of negative association with pH (odds ratio 2.001, 95% CL). PCR amplification confirmed the presence of <i>Naegleria</i> spp. in three zones: Lahore canal and swimming pools. Our study indicates the presence of <i>Naegleria</i> spp. in drinking water distribution systems of Lahore; therefore, we recommend a routine screening for <i>N. fowleri</i> in order to reduce the risk of acquiring the fatal primary amoebic meningoencephalitis infection.