Investigation of the Prevalence of Legionella in Apartment Houses

ƒThis is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/ license/by-nc/3.0/). Apartment houses is typical residential type of South Korea and was presumed the route of infection of legionellosis. But data on the management status and the risk of infection about apartment houses is lack. Therefore, we tried to investigate of prevalence and risk factors of Legionella in apartment houses. This study examined 111 samples collected from 37 apartment houses (37 hot water, 37 cold water, 37 sediments inside of faucets) and 142 hot water samples collected from 142 public-use facilities. As a result, nine of 37 apartment houses were contaminated with Legionella in only hot water and two were contaminated with Legionella in hot water and faucets. The prevalence of Legionella in hot water of apartment houses and public-use facilities was 29.7% and 20.4%, respectively. However, the percentages of bacteria exceeding 1,000 CFU/L was 13.5% and 16.2% in respectively. The analysis of the prevalence of Legionella by age of apartment houses showed 6.7% for 1 to 10 years, 33.3% for 10 to 20 years and 53.8% exceed 20 years. Analysis of the serotype of isolated Legionella was that two were L. pneumophila sg1, seven were L. pneumophila sg2-14, and four were Legionella spp.