Role of biofilms in the survival of Legionella pneumophila to sodium chloride treatment
Autor: | Abdelwahid Assaidi, Mostafa Ellouali, Hassan Latrache, Hafida Zahir, El Mostafa Mliji |
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Jazyk: | angličtina |
Rok vydání: | 2021 |
Předmět: | |
Zdroj: | Iranian Journal of Microbiology, Vol 13, Iss 4 (2021) |
Druh dokumentu: | article |
ISSN: | 2008-3289 2008-4447 |
DOI: | 10.18502/ijm.v13i4.6973 |
Popis: | Background and Objectives: Legionnaires’ disease continues to be a public health concern. Colonized water distribution systems are often implicated in Legionella transmission, despite the use of various disinfection strategies, the bacterium is capable to persist and survive in water systems. The aim of this study was to investigate the persistence of Legionella pneumophila to sodium chloride over time at different temperatures and analysing the role of biofilms in the survival of this bacteria. Materials and Methods: L. pneumophila serogroup 1 and L. pneumophila serogroup 2-15 were used to study the effect of sodium chloride on planktonic and sessile cells. The tested concentrations were: 0.5%, 1%, 2%, 3%, 4%, 6% and 8% (W/V) NaCl. Biofilms were grown on 24-well microplates. Results: At 20°C, L. pneumophila planktonic cells were able to survive in sodium chloride concentrations up to 2%. However, at 37°C, a sodium chloride concentration over 1.5%, reduced systematically the numbers of bacterial cells. Biofilms were grown for 20 days in the absence and presence of sodium chloride. The results show that bacterial strains were able to survive and regrow after the sodium chloride shock (2-3%). Moreover, it seems that this effect is less expressed with the age of the biofilm; old biofilms were more persistent than the young ones. Conclusion: Results from this study demonstrate that the sodium chloride disinfection strategy was effective on Legionella pneumophila planktonic cells but not on biofilms, which demonstrate the role of biofilms in the persistence and recolonization of L. pneumophila in water distribution systems. |
Databáze: | Directory of Open Access Journals |
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