Investigation of Legionella pneumophila in drinking water

A two phase investigation into the presence of L. pneumophila in drinking water systems and domestic plumbing is described. In phase 1, 68 water samples from domestic plumbing from 17 community water systems were analysed. No L. pneumophila organisms were found. In the second phase, kitchen sink taps, aerators, shower heads and supply pipes were swabbed and analysed together with samples from the hot water systems. From the 184 samples examined, L. pneumophila was isolated from 2 water heaters. One of these was in a community water supply and one was fed from a shallow well. L. pneumophila might be transported from natural aquatic sources via distribution systems in very low concentrations to house water heaters. There are 56 references.