Microbial quality of water in rural communities of Trinidad

RESUMO

A cross-sectional study was conducted in four rural communities of northeastern Trinidad to determine the microbial quality of water supply to households and that quality's relationship to source and storage device. Of the 167 household water samples tested, total coliforms were detected in 132 of the samples (79.0 por cent), fecal coliforms in 102 (61.1 por cent), and E. coli in 111 (66.5 por cent). There were significant differences among the towns in the proportion of the samples contaminated with coliforms (P < 0.001) and E. coli (P < 0.001). Of 253 strains of E. coli studied, 4 (1.6 por cent) were mucoid, 9 (3.6 por cent) were hemolytic, and 37 (14.6 por cent) were nonsorbitol fermenters. Of 69 isolates of E. coli tested, 10 (14.5 por cent) were verocytotoxigenic. Twenty-eight (14.0 por cent) of 200 E. coli isolates tested belonged to enteropathogenic serogroups. Standpipe, the most common water source, was utilized by 57 (34.1 por cent) of the 167 households. Treated water (pipeborne in homes, tandpipes, or truckborne) was supplied to 119 households (71.3 por cent), while 48 households (28.7 por cent) used water from untreated sources (rain, river/stream, or well) as their primary water supply. The type of household storage device was associated with coliform contamination. Water stored in drums, barrels, or buckets was more likely to harbor fecal coliforms (74.2 por cent of samples) htan was water stored in tanks (53.3 por cent of samples), even after controlling for water source (P = 0.04). Compared with water from other sources, water piped into homes was significantly less likely to be contaminated with total coliforms (56.9 por cent) versus 88.8 por cent, P<0.001) and fecal coliforms (41.2 por cent versus 69.8 por cent, P<0.01), even when the type of storage device was taken into account. However, fecal contamination was not associated with whether the water came from a treated or untreated source. We concluded that the drinking water in rural communities in Trinidad was grossly unfit for human consumption, due both to contamination of vaious water sources and during household water storage