The detection of Cryptosporidium oocysts and Giardia cysts in cistern water in the U.S. Virgin Islands

摘要: Most homes and public facilities in the U.S. Virgin Islands use a roof catchment system to obtain drinking water. Because water is so scarce throughout islands, every building (except those federally owned) are required have cistern. Rainwater collected cisterns subject contamination from enteric pathogens found environment. The objective of this study was determine occurrence concentrations human protozoa originating animal fecal contamination. Volumes 400 1 were filtered nine private four times over 1-year period for total 44 samples. After processing filter, entire volume examined using Cryptosporidium Giardia specific antibodies epifluorescence microscopy levels oocysts cysts. One or both 81% statistically significant (P = 0.005) when compared where 47% samples positive. more often than Giardia. In addition, polyclonal antibody which genera-specific, also detected monoclonal species-restrictive C. parvum, associated with disease humans, suggesting that non-mammalian frequently cistern waters. Levels ranged 10 organisms/100 one sample at 70 oocysts. These estimated daily risks 10−2 10−4 well above acceptable guidance as described safe United States. On occasion high heterotrophic bacteria (9.9 × 105 CFU/ml) coliforms (> 2000 CFU/100 ml) these A correlation between detection spp. (r 0.47853, P 0.0008). results show Giardia, bacteria, present waters may involve health risks. Public systems particular concern because percentage contaminated greater number people exposed.