title: Clinical characteristics and outcomes of influenza and other influenza-like illnesses in Mexico City.
abstract: BACKGROUND
  Influenza-like illnesses (ILI) are estimated to cause millions of deaths annually. Despite this disease burden, the etiologic causes of ILI are poorly described for many geographical regions.
  
  
  METHODS
  Beginning in April 2010, we conducted an observational cohort study at five hospitals in Mexico City, enrolling subjects who met the criteria for ILI. Evaluations were conducted at enrollment and on day 28, with the collection of clinical data and a nasopharyngeal swab (or nasal aspirate in children). Swabs were tested by multiplex PCR for 15 viral pathogens and real-time PCR for influenza.
  
  
  RESULTS
  During the first year, 1065 subjects were enrolled in this study, 55% of whom were hospitalized; 24% of all subjects were children. One or more pathogens were detected by PCR in 64% of subjects, most commonly rhinovirus (25% of all isolates) and influenza (24% of isolates). Six percent of subjects died, and of those, 54% had no pathogen identified. Rhinovirus was the most common pathogen among those who died, although it did not have the highest case fatality rate.
  
  
  CONCLUSIONS
  Multiple respiratory viruses beyond influenza are associated with significant morbidity and mortality among adults and children in Mexico City. Detection of these agents could be useful for the adjustment of antibiotic treatment in severe cases.
authors: Instituto Nacional de Ciencias de Médicas y Nutrición Salvador Zubirán, Vasco de Quiroga 15, Col. Sección XVI, Mexico City, DF 14000, Mexico. galindofraga@yahoo.com
authors: Arturo
authors: A
authors: Galindo-Fraga
authors: Ana A
authors: AA
authors: Ortiz-Hernández
authors: Alejandra
authors: A
authors: Ramírez-Venegas
authors: Rafael Valdez
authors: RV
authors: Vázquez
authors: Sarbelio
authors: S
authors: Moreno-Espinosa
authors: Beatriz
authors: B
authors: Llamosas-Gallardo
authors: Santiago
authors: S
authors: Pérez-Patrigeon
authors: Maggie
authors: M
authors: Salinger
authors: Laura
authors: L
authors: Freimanis
authors: Chiung-yu
authors: CY
authors: Huang
authors: Wenjuan
authors: W
authors: Gu
authors: M Lourdes
authors: ML
authors: Guerrero
authors: John
authors: J
authors: Beigel
authors: Guillermo M
authors: GM
authors: Ruiz-Palacios
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D017934:Coronavirus / Q000235:genetics / Q000302:isolation & purification; D018352:Coronavirus Infections / Q000453:epidemiology*; D004279:DNA, Viral / Q000032:analysis; D003937:Diagnosis, Differential; D005260:Female; D017052:Hospital Mortality; D006760:Hospitalization / Q000706:statistics & numerical data; D006801:Humans; D007223:Infant; D007251:Influenza, Human / Q000453:epidemiology*; D008297:Male; D008800:Mexico / Q000453:epidemiology; D008875:Middle Aged; D060885:Multiplex Polymerase Chain Reaction; D009975:Orthomyxoviridae / Q000235:genetics / Q000302:isolation & purification; D010850:Picornaviridae Infections / Q000453:epidemiology*; D060888:Real-Time Polymerase Chain Reaction; D018357:Respiratory Syncytial Virus Infections / Q000453:epidemiology*; D018113:Respiratory Syncytial Virus, Human / Q000235:genetics / Q000302:isolation & purification; D012229:Rhinovirus / Q000235:genetics / Q000302:isolation & purification; D055815:Young Adult
chemical_list: D004279:DNA, Viral