title: [Microorganisms responsible of nosocomial infections in the Mexican Social Security Institute].
abstract: BACKGROUND
  The prevention and control of the nosocomial infections involve the knowledge of the most frequent type of microorganism isolated. In Mexico there are not national statistics to identify the main microorganisms that cause a nosocomial infection.
  
  
  METHODS
  It was conducted an analysis of all the culture results of the nosocomial infections reported by the Sistema de Vigilancia Epidemiológica Hospitalaria (Epidemiological Surveillance System) of the Instituto Mexicano del Seguro Social during the year 2013. The most frequent and relevant microorganisms were reported.
  
  
  RESULTS
  48 377 results from cultures of nosocomial infections were studied. Of these 13 207 (27.3 %) were from 25 high specialty medical units and 35 170 (72.6 %) from 197 second level medical units. The most frequently isolated microorganism was Escherichia coli with 8192 results (16.9 %), followed by the group of Coagulase-negative Staphylococci with 6771 cultures (14 %) and Pseudomonas aeruginosa with 5275 results (19.9 %). Slight differences between levels of care and specialized hospitals were observed.
  
  
  CONCLUSIONS
  This study identifies the Escherichia coli, the group of Coagulase-negative Staphylococci and the Pseudomonas aeruginosa as the main microorganisms to prevent.
authors.affiliation: Área de Vigilancia Epidemiológica Hospitalaria, División de Enfermedades Transmisibles, Coordinación de Vigilancia Epidemiológica, Instituto Mexicano del Seguro Social, Distrito Federal, México. rafael.arias@imss.gob.mx.
authors.forename: Rafael
authors.initials: R
authors.lastname: Arias-Flores
authors.forename: Ulises
authors.initials: U
authors.lastname: Rosado-Quiab
authors.forename: Alfredo
authors.initials: A
authors.lastname: Vargas-Valerio
authors.forename: Concepción
authors.initials: C
authors.lastname: Grajales-Muñiz
mesh_terms: D000047:Academies and Institutes; D002177:Candidiasis / Q000175:diagnosis / Q000453:epidemiology* / Q000517:prevention & control; D003428:Cross Infection / Q000175:diagnosis / Q000453:epidemiology / Q000382:microbiology* / Q000517:prevention & control; D004927:Escherichia coli Infections / Q000175:diagnosis / Q000453:epidemiology / Q000517:prevention & control; D016905:Gram-Negative Bacterial Infections / Q000175:diagnosis / Q000453:epidemiology* / Q000517:prevention & control; D016908:Gram-Positive Bacterial Infections / Q000175:diagnosis / Q000453:epidemiology* / Q000517:prevention & control; D006801:Humans; D017053:Infection Control; D008800:Mexico / Q000453:epidemiology; D011552:Pseudomonas Infections / Q000175:diagnosis / Q000453:epidemiology / Q000517:prevention & control; D011550:Pseudomonas aeruginosa / Q000302:isolation & purification; D012943:Social Security; D013203:Staphylococcal Infections / Q000175:diagnosis / Q000453:epidemiology / Q000517:prevention & control
keywords: Bacterial infections; Cross infection; Mexico; Mycoses; Social security