TY - JOUR
T1 - Co‐occurrence of free‐living amoeba and legionella in drinking water supply systems
AU - Valciņa, Olga
AU - Pūle, Daina
AU - Mališevs, Artjoms
AU - Trofimova, Jūlija
AU - Makarova, Svetlana
AU - Konvisers, Genadijs
AU - Bērziņš, Aivars
AU - Krūmiņa, Angelika
N1 - Funding Information:
Funding: This study was funded by National Research Programme No. 7, Agricultural Resources for Sustainable Production of Qualitative and Healthy Foods in Latvia project No. 5 “Resistance of microorganisms and other biological and chemical risks: research procedure development and application in the food chain.”
Publisher Copyright:
© 2019 by the authors. Licensee MDPI, Basel, Switzerland.
PY - 2019/8
Y1 - 2019/8
N2 - Background and Objectives: Legionella is one of the most important water-related pathogens. Inside the water supply systems and the biofilms, Legionella interact with other bacteria and free-living amoeba (FLA). Several amoebas may serve as hosts for bacteria in aquatic systems. This study aimed to investigate the co-occurrence of Legionella spp. and FLA in drinking water supply systems. Materials and Methods: A total of 268 water samples were collected from apartment buildings, hotels, and public buildings. Detection of Legionella spp. was performed in accordance with ISO 11731:2017 standard. Three different polymerase chain reaction (PCR) protocols were used to identify FLA. Results: Occurrence of Legionella varied from an average of 12.5% in cold water samples with the most frequent occurrence observed in hot water, in areas receiving untreated groundwater, where 54.0% of the samples were Legionella positive. The occurrence of FLA was significantly higher. On average, 77.2% of samples contained at least one genus of FLA and, depending on the type of sample, the occurrence of FLA could reach 95%. In the samples collected during the study, Legionella was always isolated along with FLA, no samples containing Legionella in the absence of FLA were observed. Conclusions: The data obtained in our study can help to focus on the extensive distribution, close interaction, and long-term persistence of Legionella and FLA. Lack of Legionella risk management plans and control procedures may promote further spread of Legionella in water supply systems. In addition, the high incidence of Legionella-related FLA suggests that traditional monitoring methods may not be sufficient for Legionella control.
AB - Background and Objectives: Legionella is one of the most important water-related pathogens. Inside the water supply systems and the biofilms, Legionella interact with other bacteria and free-living amoeba (FLA). Several amoebas may serve as hosts for bacteria in aquatic systems. This study aimed to investigate the co-occurrence of Legionella spp. and FLA in drinking water supply systems. Materials and Methods: A total of 268 water samples were collected from apartment buildings, hotels, and public buildings. Detection of Legionella spp. was performed in accordance with ISO 11731:2017 standard. Three different polymerase chain reaction (PCR) protocols were used to identify FLA. Results: Occurrence of Legionella varied from an average of 12.5% in cold water samples with the most frequent occurrence observed in hot water, in areas receiving untreated groundwater, where 54.0% of the samples were Legionella positive. The occurrence of FLA was significantly higher. On average, 77.2% of samples contained at least one genus of FLA and, depending on the type of sample, the occurrence of FLA could reach 95%. In the samples collected during the study, Legionella was always isolated along with FLA, no samples containing Legionella in the absence of FLA were observed. Conclusions: The data obtained in our study can help to focus on the extensive distribution, close interaction, and long-term persistence of Legionella and FLA. Lack of Legionella risk management plans and control procedures may promote further spread of Legionella in water supply systems. In addition, the high incidence of Legionella-related FLA suggests that traditional monitoring methods may not be sufficient for Legionella control.
KW - Amoeba
KW - Co-occurrence
KW - Legionella
KW - Protozoa
KW - Water
UR - http://www.scopus.com/inward/record.url?scp=85071489289&partnerID=8YFLogxK
U2 - 10.3390/medicina55080492
DO - 10.3390/medicina55080492
M3 - Article
C2 - 31443316
AN - SCOPUS:85071489289
SN - 1010-660X
VL - 55
JO - Medicina (Lithuania)
JF - Medicina (Lithuania)
IS - 8
M1 - 492
ER -