Bacteriological Analysis of Water in a Medical College to Assess its Possible Role in Hospital Infections

Assessment of bacteriological quality of water collected from a new medical college set up was undertaken. Water samples were collected from overhead storage tanks, drinking water sources and laboratory taps. Bacteriological contamination of different water sources was assessed by most probable number (MPN) technique and simultaneously identifying the presence of any faecal coliform or other bacteria, if any. A total 273 samples were examined from overhead tanks (n= 17), Reverse Osmosis (RO) water purifier outlets for drinking water (n= 56) and normal taps at the laboratories, wash basins (n= 200). Out of the total water samples collected, 5.5% (n= 15) of the samples were of excellent quality (MPN=0/dl), 24.5% (n= 67) of the samples were of satisfactory quality (MPN=1-3/dl), 41.1% (n= 112) were of unsatisfactory quality (MPN ³ 10/dl) while 28.9% (n= 79) were of suspicious quality (MPN 4-9/dl). In 48.7% (n= 133) of the water samples, faecal coliform contamination was detected while Pseudomonas aeruginosa was isolated from 65.5% (n= 179) of the samples. Both suspicious and unsatisfactory quality of water samples showed faecal contamination, whereas Ps. aeruginosa was isolated from all categories of samples except excellent quality. Bacteriological contamination of water, especially drinking water and its sources are regarded as having the potential to have negative health effects on consumers. Therefore, before consumers use the water sources, sufficient filtration and treatment must be provided.