Details
| Original language | English |
|---|---|
| Pages (from-to) | 315-322 |
| Number of pages | 8 |
| Journal | International Journal of Hygiene and Environmental Health |
| Volume | 221 |
| Issue number | 2 |
| Early online date | 14 Dec 2017 |
| Publication status | Published - Mar 2018 |
Abstract
The occurrence of Legionella pneumophila in activated sludge systems has been reported in the literature. However, the factors triggering its growth are not yet well understood. This knowledge is needed to develop strategies to minimize the risk of the spread of Legionnaires’ disease that originates in these systems. In the present study, L. pneumophila multiplied exponentially at 35 °C in activated sludge, but lower temperatures (24 °C and 15 °C) did not favour the growth of the pathogen despite the presence of its protozoan hosts (free-living amoeba and ciliates). L. non-pneumophila species, which are adapted to low temperature, prevailed at 15 °C. Legionella was found dispersed in the activated sludge, forming clusters of different sizes and also inside protozoa. This study shows that temperature is a key parameter triggering the growth of L. pneumophila in activated sludge. The detection of infected protozoa suggests that these are important vehicles for the multiplication of Legionella. However, in this study it was not possible to exclude the growth of Legionella directly on the substrate or on the activated sludge matrix.
Keywords
- Activated sludge, Free-living amoeba, Legionella pneumophila, Temperature
ASJC Scopus subject areas
- Medicine(all)
- Public Health, Environmental and Occupational Health
Sustainable Development Goals
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In: International Journal of Hygiene and Environmental Health, Vol. 221, No. 2, 03.2018, p. 315-322.
Research output: Contribution to journal › Article › Research › peer review
}
TY - JOUR
T1 - Temperature-driven growth of Legionella in lab-scale activated sludge systems and interaction with protozoa
AU - Caicedo, C.
AU - Rosenwinkel, K. H.
AU - Nogueira, R.
N1 - Publisher Copyright: © 2017 Elsevier GmbH Copyright: Copyright 2018 Elsevier B.V., All rights reserved.
PY - 2018/3
Y1 - 2018/3
N2 - The occurrence of Legionella pneumophila in activated sludge systems has been reported in the literature. However, the factors triggering its growth are not yet well understood. This knowledge is needed to develop strategies to minimize the risk of the spread of Legionnaires’ disease that originates in these systems. In the present study, L. pneumophila multiplied exponentially at 35 °C in activated sludge, but lower temperatures (24 °C and 15 °C) did not favour the growth of the pathogen despite the presence of its protozoan hosts (free-living amoeba and ciliates). L. non-pneumophila species, which are adapted to low temperature, prevailed at 15 °C. Legionella was found dispersed in the activated sludge, forming clusters of different sizes and also inside protozoa. This study shows that temperature is a key parameter triggering the growth of L. pneumophila in activated sludge. The detection of infected protozoa suggests that these are important vehicles for the multiplication of Legionella. However, in this study it was not possible to exclude the growth of Legionella directly on the substrate or on the activated sludge matrix.
AB - The occurrence of Legionella pneumophila in activated sludge systems has been reported in the literature. However, the factors triggering its growth are not yet well understood. This knowledge is needed to develop strategies to minimize the risk of the spread of Legionnaires’ disease that originates in these systems. In the present study, L. pneumophila multiplied exponentially at 35 °C in activated sludge, but lower temperatures (24 °C and 15 °C) did not favour the growth of the pathogen despite the presence of its protozoan hosts (free-living amoeba and ciliates). L. non-pneumophila species, which are adapted to low temperature, prevailed at 15 °C. Legionella was found dispersed in the activated sludge, forming clusters of different sizes and also inside protozoa. This study shows that temperature is a key parameter triggering the growth of L. pneumophila in activated sludge. The detection of infected protozoa suggests that these are important vehicles for the multiplication of Legionella. However, in this study it was not possible to exclude the growth of Legionella directly on the substrate or on the activated sludge matrix.
KW - Activated sludge
KW - Free-living amoeba
KW - Legionella pneumophila
KW - Temperature
UR - http://www.scopus.com/inward/record.url?scp=85039742609&partnerID=8YFLogxK
U2 - 10.1016/j.ijheh.2017.12.003
DO - 10.1016/j.ijheh.2017.12.003
M3 - Article
C2 - 29279237
AN - SCOPUS:85039742609
VL - 221
SP - 315
EP - 322
JO - International Journal of Hygiene and Environmental Health
JF - International Journal of Hygiene and Environmental Health
SN - 1438-4639
IS - 2
ER -