1- 2- 1- Isolation of Acanthamoeba species from fresh water sources in southern regions of Saudi Arabia


Objective: The present study aimed to investigate the occurrence of Acanthamoeba species and other FLAs in freshwater sources in southern regions of the Kingdom of Saudi Arabia and to estimate the prevalence of their existence in these areas.
Methods: Water samples from both fresh water course and hot springs (n = 15) were collected from five different zones in Aseer region, southern western parts of the kingdom. Isolation and identification of Acanthamoeba species and other FLAs were carried out from these water sources (fresh water course and hot spring). The methods included filtration, in vitro culture and incubation for up to three weeks for the selected samples according to standard methods.
Results: Examination of water samples by direct microscopic methods showed no amoebic parasites among all of the 15 samples collected from five different sites. However, when the water samples were cultured on non-nutrient agar (NNA), four (26.7%) of the 15 samples showed growth of Acanthamoeba species. Principle component analysis (PCA) indicated that the water bodies/ sources that were positive for Acanthamoeba spp. shared a common natural characteristic that the water bodies were exposed to contamination.
Conclusion: The study demonstrated that Acanthamoeba spp. were prevalent in some sites (3 out 5 sites were positives; 60%), low in two sites (1 out 3 samples) while absent in two sites (0 out of six samples). More comprehensive research is needed to find out the true prevalence of these parasites and factors affecting their existence.