Distribution of Legionella Species from Environmental Water Sources of Public Facilities and Genetic Diversity of L. pneumophila Serogroup 1 in South Korea

다국어 초록 (Multilingual Abstract)

<B>ABSTRACT</B><P>A total of 560 <I>Legionella</I> species were isolated from environmental water sources from public facilities from June to September 2008 throughout South Korea. The distribution of <I>Legionella</I> isolates was investigated according to geographical region, facility type, and sample type. The genetic diversity of 104 isolates of <I>Legionella pneumophila</I> serogroup 1 (sg 1) was analyzed by sequence-based typing (SBT). <I>L. pneumophila</I> was distributed broadly throughout Korea, accounting for 85.0% of the isolates, and <I>L. pneumophila</I> sg 1 predominated in all of the public facilities except for the springs. <I>Legionella anisa</I> and <I>Legionella bozemanii</I> predominated among non-<I>L. pneumophila</I> species (48.1% and 21.0%, respectively). The second most dominant strain differed depending on the facility type: <I>L. anisa</I> was the second most dominant strain in the buildings (10.8%), <I>L. pneumophila</I> sg 5 in public baths (21.6%), <I>L. pneumophila</I> sg 6 in factories (12.0%), and <I>L. pneumophila</I> sg 7 in hospitals (13.1%). In the SBT analysis, 104 <I>L. pneumophila</I> sg 1 isolates were differentiated into 26 sequence types (STs) and categorized into 3 clonal groups (CGs) and 10 singleton STs via the eBURST V3 program. ST1, a potential founder of major CG1, was commonly distributed (48.1%). The dominant ST in hot water was ST-K1 (7, 12, 17, 3, 35, 11, 11), which was designated in this study (36.1%). The second most dominant strain differed depending on the type of facility from which the samples were obtained. The unique allelic profile of ST-K1, obtained from hot water, was not found in the European Working Group for <I>Legionella</I> Infections (EWGLI) SBT database.</P>