The effect of iron on the survival of Vibrio cholerae O1 in dechlorinated tap water

Many factors, such as temperature, pH, organic nutrients, types of water storage containers, etc., determine the survival of Vibrio cholerae in water. Since the survival of V. cholerae O1 has been shown to be much longer in metal drums used as household water storage containers than in clay pots and plastic drums, the present study was designed to explore the possible role played by insoluble iron on the survival of V. cholerae O1 in water. The possibility of iron acting as particulate matter for the organisms to adhere to was also examined by using inert glass beads in water. Survival of V. cholerae O1 in dechlorinated tap water, with and without inert glass beads, ranged from < 24 h to 10 d. The number of surviving bacteria was, however, very low. In the presence of impure ferric oxide (Fe2O3), survival in tap water ranged from 4 to 12 d and the numbers of surviving bacteria were very high. Iron was thought to play an important role in the survival of V. cholerae O1 in water. Differences between the numbers of bacteria and the length of survival in surface water and in sediment were unremarkable. The El Tor and classical biotypes gave similar results.