Prevalence and concentration of non-tuberculous mycobacteria in cooling towers by means of quantitative PCR: a prospective study.
There is an increasing level of interest in non-tuberculous mycobacteria (NTM) due to the increasing reported rates of diseases caused by them. Although it is well known that NTM are widely distributed in the environment it is necessary to identify its reservoirs to prevent possible infections. In this study, we aimed to investigate the occurrence and levels of NTM in cooling towers to provide evidences for considering these settings as possible sources of respiratory infections. In the current study, we detected and quantified the presence of NTM by means of a rapid method in water samples taken from 53 cooling towers of an urban area (Barcelona, Spain). A genus-specific quantitative PCR (Q-PCR) assay with a quantification limit (QL) of 500 cells l(-1) was used. 56% (30) of samples were positive with a concentration range from 4.6 × 10(3) to 1.79 × 10(6) cells l(-1). In some cases (9/30), samples were positive but with levels below the QL. The colonization rate confirmed that cooling towers could be considered as a potential reservoir for NTM. This study also evaluated Q-PCR as a useful method to detect and quantify NTM in samples coming from environmental sources.
Adrados
Bárbara
B
Laboratori de Microbiologia Sanitària i Mediambiental, Departament d'Optica i Optometria, Universitat Politècnica de Catalunya, Edifici Gaia - Pg. Ernest Lluch/Rambla Sant Nebridi, 08222, Terrassa, Barcelona, Spain. barbara.adrados@upc.edu
Julián
Esther
E
Codony
Francesc
F
Torrents
Eduard
E
Luquin
Marina
M
Morató
Jordi
J
D058491:Bacterial Load / Q000379:methods*; D006801:Humans; D009161:Mycobacterium / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification*; D016133:Polymerase Chain Reaction / Q000379:methods*; D015995:Prevalence; D011446:Prospective Studies; D013030:Spain; D014871:Water Microbiology