A lack of
sewage treatment contaminates
water bodies threatening
human health by spreading waterborne
gastroenteritis . This is a particular problem for
developing countries , where the
risks associated with
surface water contamination remain largely unknown. To understand the
risk associated with
sewage contamination of
water bodies, we evaluated the microbiological
indicators of
water quality and isolated bacterial
strains from
water bodies from the city of Belém, Pará,
Brazil . The
strains were identified by biochemical and
serological tests and
polymerase chain reactions (PCRs). The thermotolerant
coliforms and
Escherichia coli presented values above 1,000 (NMP/ 100 mL) biweekly from August 2012 to November 2015, without a significant statistical difference between sampling periods (KruskalWallis p > 0.05). The
water of the Tucunduba
river presented
contamination levels
similar to those in a
sewage pumping station (Dunn test p > 0.05). From 240 bacterial isolates, we identified 163
Vibrio cholerae , 8
Vibrio mimicus , 24 E. coli, and 5
Salmonella spp. The isolates of V. cholerae demonstrated N-
acetylglucosamine (NAG) profile (Non-O1 and NonO139) and 18 expressed the stn/sto
gene . No E. coli was shown to be potentially pathogenic. The results revealed that
water bodies in Belém were constantly contaminated by
sewage and fecal microorganisms, including the potential circulation of pathogens in viable and cultivable form.