Bacteriological quality of bottled water obtained from Mexico City small water purification plants: Incidence and identification of potentially pathogenic nontuberculous mycobacteria species.

The aim of this study was to determine the bacteriological quality of bottled water samples obtained from small purification plants located in Mexico City and to identify potentially pathogenic nontuberculous mycobacteria (NTM) species found in these samples. All 111 samples analyzed were positive for aerobic mesophilic bacteria (AMB) and 46 (41.4%) did not comply with Mexico's Official Guidelines. Sixty-nine (62.1%) and 23 (20.7%) water samples were positive for total coliforms (TC) and fecal coliforms (FC), respectively. A total of 81 (72.9%) of the water samples exceeded the maximum allowed limit stipulated in the guideline. Thirty-three (29.7%) of the purified water samples were positive for NTM, being recovered a total of 40 isolates. These NTM isolates were identified using three molecular markers (hsp65, rrs and rpoB genes) which corresponded to the fast-growing mycobacteria M. chelonae (n = 12), M. porcinum (n = 8), M. senegalense (n = 5), M. abscessus (n = 4), M. septicum (n = 4), M. wolinskyi (n = 3), M. mucogenicum (n = 2), M. fortuitum (n = 1) and M. sp. (n = 1). In seven purified water samples, two different NTM species were isolated simultaneously. Overall, these results showed that most of the purified bottled water samples analyzed in this study had unsatisfactory microbiological quality and some harbored NTM associated with illness. Our data could hasten health authorities to intensify efforts in the routine monitoring of activities in the purified bottled water industry in order to supply safe and healthy water to the public.

Cerna-Cortes JF ，Cortes-Cueto AL ，Villegas-Martínez D ，Leon-Montes N ，Salas-Rangel LP ，Rivera-Gutierrez S ，Lopez-Hernandez D ，Helguera-Repetto AC ，Fernandez-Rendon E ，Gonzalez-Y-Merchand JA ... -  《-》

Microbiological Quality of Ready-to-Eat Vegetables Collected in Mexico City: Occurrence of Aerobic-Mesophilic Bacteria, Fecal Coliforms, and Potentially Pathogenic Nontuberculous Mycobacteria.

Cerna-Cortes JF ，Leon-Montes N ，Cortes-Cueto AL ，Salas-Rangel LP ，Helguera-Repetto AC ，Lopez-Hernandez D ，Rivera-Gutierrez S ，Fernandez-Rendon E ，Gonzalez-y-Merchand JA ... -  《-》

Occurrence of potentially pathogenic nontuberculous mycobacteria in Mexican household potable water: a pilot study.

Perez-Martinez I ，Aguilar-Ayala DA ，Fernandez-Rendon E ，Carrillo-Sanchez AK ，Helguera-Repetto AC ，Rivera-Gutierrez S ，Estrada-Garcia T ，Cerna-Cortes JF ，Gonzalez-Y-Merchand JA ... -  《-》

Presence of Indicator Bacteria and Occurrence of Potentially Pathogenic Nontuberculous Mycobacteria Species in Packaged Ice Cubes in Central Mexico.

This study aimed to determine the bacteriological quality and presence of diarrheagenic Escherichia coli pathotypes (DEP) and nontuberculous mycobacteria (NTM) species in 85 packaged ice samples from 12 different states of central Mexico. Three samples had a pH of 9.8 and therefore fell outside of the acceptable range for pH. All samples were positive for aerobic-mesophilic bacteria, with limits ranging from 1 to 3.47 log CFU/mL. In total, 35, 11, and 3 ice samples were positive for total coliforms (TC), fecal coliforms (FC), and E. coli, respectively. In the samples, the TC concentration ranged from <1.1 to >23 MPN/100 mL and from <1.1 to 23 MPN/100 mL for FC and E. coli. In total, 38 (44.7%) ice samples were outside of Mexico's official guidelines. None of the 12 E. coli strains isolated from the three ice samples belonged to DEP. NTM were recovered from 20 ice samples and included M. neoaurum (n = 7), M. porcinum (n = 2), M. flavescens (n = 2), M. fortuitum (n = 1), M. abscessus (n = 1), M. senegalense (n = 1), M. conceptionense (n = 1), and M. sp. (n = 1). In the remaining four samples, two NTM were isolated simultaneously. Thus, we recommend that producers should evaluate the microbiological quality of purified water used as a raw material as well as that of the final product, the ice should be packed in thick bags to avoid stretching and tearing during transportation or storage to prevent environmental contamination of ice, personnel involved in the production, and handling of ice should be trained in relative hygiene matters and how ice-machines should be cleaned and disinfected and the implementation of hazard analysis and critical control points must be applied throughout the chain of production. Finally, regular inspection by the authorities is also of great importance. These recommendations can be applied in different countries with low microbiological quality packaged ice.

Castro-Morales O ，Soria-Herrera RJ ，Cornejo-Estudillo G ，Avila-Trejo AM ，Valencia-Trujillo D ，Zanella-Vargas MG ，Vázquez-Barrios ME ，Rangel-Vargas E ，Castro-Rosas J ，García-Reyes RL ，Rivera-Gutiérrez S ，Campos-Peña V ，Cerna-Cortés JF ... -  《-》

Microbiological Quality and Occurrence of Nontuberculous Mycobacteria in Fresh-Squeezed Orange Juice Samples Purchased from Street Vendors in Mexico City.

Cerna-Cortes JF ，Cortes-Cueto AL ，Cano-Gaona MR ，Leon-Montes N ，Helguera-Repetto AC ，Rivera-Gutierrez S ，Salas-Rangel LP ，Castro-Rosas J ，Gonzalez-Y-Merchand JA ... -  《-》