Seasonal variation of Legionella in Taiwan's reservoir and its relationships with environmental factors.
In this study, the presence of Legionella in major water reservoirs of Taiwan was examined with respect to seasonal variation, geographical variation, and water quality parameters using TaqMan real-time qPCR. Water samples were collected quarterly at 19 reservoirs in Taiwan between November 2012 and August 2013. The detection rate for Legionella was 35.5% (27/76), and Legionella was detected in all seasons. The Legionella concentration was relatively high in spring and summer, reaching 3.86 × 10(8) and 7.35 × 10(8) cells/L, respectively. By sampling the area, Legionella was detected at a higher proportion in reservoirs in the northern and southern areas, and the difference was consistent in all seasons. Significant association was found between detection of Legionella and various water quality parameters, including conductivity, chlorophyll a, and dissolved oxygen (Mann-Whitney U test, P < 0.05). Results of Spearman rank test showed negative correlation for Legionella detection with pH (P = 0.030, R = -0.497) and dissolved oxygen (P = 0.007, R = -0.596) in fall and positive correlation with Carlson's trophic state index (P = 0.049, R = 0.457) in spring. The identified species included Legionella pneumophila and Legionella drancourtii. The detection of Legionella in reservoirs was indicative of a potential public health risk and should be further evaluated.
Department of Earth and Environmental Sciences, National Chung Cheng University, Chiayi, Taiwan, Republic of China.
Po-Min
PM
Kao
Bing-Mu
BM
Hsu
Tien-Yu
TY
Chang
Tsui-Kang
TK
Hsu
Kai-Jiun
KJ
Tzeng
Yu-Li
YL
Huang
D002734:Chlorophyll / Q000502:physiology; D000077194:Chlorophyll A; D017931:DNA Primers / Q000235:genetics; D004553:Electric Conductivity; D004777:Environment; D004784:Environmental Monitoring / Q000379:methods / Q000706:statistics & numerical data*; D018628:Gene Dosage; D007875:Legionella / Q000235:genetics / Q000254:growth & development*; D010100:Oxygen / Q000032:analysis; D012335:RNA, Ribosomal / Q000235:genetics; D060888:Real-Time Polymerase Chain Reaction; D012621:Seasons; D013045:Species Specificity; D018709:Statistics, Nonparametric; D013624:Taiwan; D014871:Water Microbiology; D014881:Water Supply / Q000592:standards*
D017931:DNA Primers; D012335:RNA, Ribosomal; D002734:Chlorophyll; D010100:Oxygen; D000077194:Chlorophyll A