“…In Mexico, the indicators of the microbiological contamination level in drinking water for human utilization and consumption, are based on the determination of total and fecal coliforms regulated by the Mexican Official Standards NOM-127-SSA1-1994 and NMX-AA-042-SCFI-2015; (CONAGUA, 2016;Galdos, 2017). In this way, the presence of enterobacteria such as Escherichia coli, Shigella, Salmonella or mesophilic aerobic microorganisms indicates pollution in drinking water, because they cause gastrointestinal diseases like hemorrhagic colitis, bloody diarrhea, dysentery, invasive enteritis, typhoid, gastroenteritis, bacteremia and salmonellosis (Baker, 2018;Clements, 2012;Johnson, 2018;Lampel, 2018 andRamos, 2008). The intensity of symptoms will depend on the susceptibility of the human host and the pathogenic capacity of bacteria (Rios, 2019;Rios, 2017 andPulles, 2014).…”