title: [Epidemic of pneumonia associated with mechanical ventilation in Mérida, Yucatán].
abstract: OBJECTIVE
  To determine the main epidemiological, clinical, and microbiologic characteristics of an outbreak of ventilator-associated pneumonia at an intensive care unit in Yucatan.
  
  
  METHODS
  An 11-month prospective and observational study was designed to determine incidence, mortality, potential reservoirs, etiologic agents and antibiotic susceptibility patterns.
  
  
  RESULTS
  The incidence of ventilator-associated pneumonia was 74%. The crude mortality rate was 88% compared to a 19.5% expected-mortality rate. Gram-negative bacteria were isolated from 98% of the cultures, of which 46% were susceptible to third generation cephalosporins, 59% to fourth generation cephalosporins, 70% to ciprofloxacin and 100% to imipenem. Klebsiella pneumoniae and Pseudomonas aeruginosa were isolated from some of the ventilator circuits and the sink.
  
  
  CONCLUSIONS
  The high incidence of pneumonia and associated mortality in our intensive care unit may be attributed to the absence of infection control measures and the high prevalence of multiresistant organisms which is related to antibiotic abuse.
authors.affiliation: Departamento de Investigación, Hospital General O'Horan, Mérida, Yucatán, México. mbzaidi@diario1.sureste.com
authors.forename: M
authors.initials: M
authors.lastname: Zaidi
authors.forename: G
authors.initials: G
authors.lastname: Martín
authors.forename: R
authors.initials: R
authors.lastname: Rosado
mesh_terms: D003428:Cross Infection / Q000453:epidemiology* / Q000209:etiology / Q000401:mortality; D004196:Disease Outbreaks; D006801:Humans; D015994:Incidence; D007362:Intensive Care Units; D008800:Mexico / Q000453:epidemiology; D011014:Pneumonia / Q000453:epidemiology* / Q000209:etiology / Q000401:mortality; D011446:Prospective Studies; D012121:Respiration, Artificial / Q000009:adverse effects*; D012621:Seasons; D013997:Time Factors