Bacteriological indicators of tropical water quality

In a search for appropriate bacterial indicators of tropical water quality using the membrane filtration technique, four bacterial groups were surveyed. Of these, Aeromonas hydrophila, Vibrio species, and fecal coliforms were consistently isolated from the four surface water sources located in southeastern Nigeria. Aeromonas hydrophila was isolated at far greater frequency than the other test organisms. It had the highest isolation frequency (60.4%) while the fecal coliform group followed with 33.3%. Fecal streptococci had the lowest frequency of isolation. It is proposed that A. hydrophila and Vibrio species be included as indicator bacteria in tropical water quality assays.