Bacteriological and Physicochemical Studies on Three Major Dams in Ekiti State, Nigeria

The bacteriological and physicochemical properties of public water supply system in Ekiti State, Nigeria were analyzed, using treated and untreated water samples from selected dams. The antibiotic sensitivity of 140 E.coli (as water indicator) isolated was evaluated using microbiological standard methods. The plasmid profile of 20 selected resistant isolates was done using agarose gel electrophoresis method. The coliform and E. coli count were apparently high with average range of 28.6x102 to 39.8x103CFU/ml and 13.0x102 to 8.4x103CFU/ml respectively. Though less than 3% of the isolated E. coli was sensitive to ofloxacin, nalixidic acid and nitrofurantoin, only 24(17.1%) was resistant to amoxicillin. Among the multidrug resistant isolates about 92.9% were resistant to at least four antibiotics while 7.0% were resistant to all the eight antibiotics used. Out of 20 MDR isolates selected, only one (1) showed absence of plasmid as other harbored plasmids ranging from 1 to 4. The size of the plasmids in kilobase pair ranged between 2.03 and 3.13. The physicochemical properties and mineral content of the water samples were all within WHO permissible limits with pH range of (7.40-7.80) and temperature range of (27.5-28.0)0C. The occurrence of plasmid-mediated multidrug resistant E. coli in a public water supply system in rural community heightens public health concern as discussed in this work. Keywords:Ureje, Ero, Egbe, multidrug resistance, plasmid mediated, physicochemica