Table 1.
Concentrations of amoebae and Legionella species increased in water samples collected from the cooling towers (CT) than in the drinking water system (RES_IN, RES_EF, Fa, and ERC). Influent, hot-, and cold-water samples were nested together for buildings Fa and ERC.
| Free-Living Amoebae | Site Location | ||||
|---|---|---|---|---|---|
| Res_In | Res_EF | Fa | ERC | CT | |
|
Acanthamoeba spp. (%) |
0/6 (0%) |
0/6 (0%) |
3/15 (20%) |
0/9 (0%) |
5/6 (83%) |
|
Acanthamoeba spp. Min, and Max Geomean (Log10 GC/100 mL) |
ND | ND | 1.1, 1.4 |
ND | 2.0, 2.5 |
|
N.fowleri (%) |
5/6 (83%) |
1/6 (16%) |
0/15 (0%) |
6/9 (66%) |
5/6 (83%) |
|
N.fowleri Min, and Max Geomean (Log10 GC/100 mL) |
1.3, 1.7 |
1.5 a | ND | 1.1, 1.8 |
1.3, 2.4 |
| Legionella Species | |||||
|
Legionella spp. (23S rRNA) (%) |
(6/6) (100%) |
(6/6) (100%) |
15/15 (100%) |
9/9 (100%) |
6/6 (100%) |
|
Legionella spp. (23S rRNA) Geomean (Log10 GC/100 mL) |
3.1 | 2.7 | 2.3 | 4.3 | 4.5 |
|
L. pneumophila (%) |
5/6 (83%) |
5/6 (83%) |
6/15 (40%) |
3/9 (33%) |
5/6 (83%) |
|
L. pneumophila Geomean (Log10 GC/100 mL) |
1.6 | 1.8 | 1.6 | 1.4 | 2.8 |
|
L. micdadei (%) |
1/6 (17%) |
0/6 (0%) |
3/15 (20%) |
4/9 (44%) |
2/6 (33%) |
|
L. micdadei Geomean (Log10 GC/100 mL) |
1.5 | ND | 1.5 | 1.6 | 2.4 |
|
L. bozemanii (%) |
4/6 (67%) |
(6/6) (100%) |
2/15 (13%) |
4/9 (44%) |
6/6 (100%) |
|
L. bozemanii Geomean (Log10 GC/100 mL) |
1.5 | 1.7 | 1.4 | 1.5 | 2.9 |
|
L. longbeachae (%) |
0/6 (0%) |
0/6 (0%) |
8/15 (53%) |
4/9 (44%) |
3/6 (50%) |
|
L. longbeachae Geomean (Log10 GC/100 mL) |
ND | ND | 1.4 | 1.4 | 1.5 |
|
L. anisa (%) |
0/6 (0%) |
0/6 (0%) |
5/15 (33%) |
0/6 (0%) |
4/6 (67%) |
|
L. anisa Geomean (Log10 GC/100 mL) |
ND | ND | 1.4 | ND | 2.1 |
a Only value detected. ND: no data.