The International Journal of Mycobacteriology

ORIGINAL ARTICLE
Year
: 2019  |  Volume : 8  |  Issue : 2  |  Page : 138--145

Prevalence and species diversity of nontuberculous mycobacteria in drinking water supply system of Bahía Blanca City, Argentina


Alejandra Soledad Oriani1, María Jimena Marfil2, Martín Jose Zumárraga2, Mónica Diana Baldini1 
1 Department of Biology, Biochemistry and Pharmacy, Southern National University, San Juan 670, Bahía Blanca, Argentina
2 Institute of Agrobiotechnology and Molecular Biology, National Scientific and Technical Research Council, National Institute of Agricultural Technology, Hurlingham, Buenos Aires, Argentina

Correspondence Address:
Alejandra Soledad Oriani
Cambaceres 1407, Bahía Blanca (8000), Buenos Aires
Argentina

Background: There is evidence that tap water is the vehicle through which nontuberculous mycobacteria (NTM) infect or colonize the human body. The objective of this study was to determine the presence and diversity of NTM in the water distribution system of Bahía Blanca city, Argentina (sites S2/S3) and in the dike that supplies water to it (S1). Methods: Culture-dependent method, biochemical tests, and molecular method (16S rRNA sequencing gene) were combined to detect and identify NTM. Results: NTM were isolated in 51.6% (64/124) of all the samples analyzed. Mycobacterium gordonae was the most frequently isolated organism (15/64) in all samples analyzed, followed by Mycobacterium peregrinum and Mycobacterium frederiksbergense. Significant differences were found in the residual chlorine values between sampling S2 and S3. In both sites, maximum counts were recorded but they did not correlate with low chlorine values. A concentration higher than 500 colony-forming unit/L of NTM was never found, which can be attributed to the negative effect caused by decontamination methods being a point to consider for the recovery of NTM. In 46.9% (30/64) of samples, both methods coincided in the identification, and the obtained sequences presented ≥99% identity. Identification at the species level was achieved in 50% (32/64) of the isolates. Nearly 17.2% (11/64) of the isolates showed a similarity <99%. Conclusions: It should be taken into account that sequencing of the 16S rRNA gene and biochemical tests are useful for the identification of several species, but it is necessary to incorporate other genes (hsp 65 and rpo B) to obtain accurate identification.


How to cite this article:
Oriani AS, Marfil MJ, Zumárraga MJ, Baldini MD. Prevalence and species diversity of nontuberculous mycobacteria in drinking water supply system of Bahía Blanca City, Argentina.Int J Mycobacteriol 2019;8:138-145


How to cite this URL:
Oriani AS, Marfil MJ, Zumárraga MJ, Baldini MD. Prevalence and species diversity of nontuberculous mycobacteria in drinking water supply system of Bahía Blanca City, Argentina. Int J Mycobacteriol [serial online] 2019 [cited 2019 Oct 22 ];8:138-145
Available from: http://www.ijmyco.org/article.asp?issn=2212-5531;year=2019;volume=8;issue=2;spage=138;epage=145;aulast=Oriani;type=0