title: Impact of a combined pediatric and adult pneumococcal immunization program on adult pneumonia incidence and mortality in Nicaragua.
abstract: BACKGROUND
  In 2010, Nicaragua implemented an adult immunization program with the 23-valent pneumococcal polysaccharide vaccine (PPSV-23) and a pediatric immunization program with the 13-valent pneumococcal conjugate vaccine (PCV-13). We assessed incidence rates of ambulatory visits and hospitalizations for pneumonia and pneumonia-related mortality in adults over the age of 50 years before and after the program's implementation in the Department of León, Nicaragua.
  
  
  METHODS
  We collected visit diagnoses from all 107 public health facilities between 2008 and 2012 in León. We compared incidence rates of ambulatory visits for pneumonia, pneumonia hospitalizations, and pneumonia-related mortality in the pre-vaccine (2008-2009) and vaccine (2011-2012) periods among older adults using Poisson regression with generalized estimating equations (GEE), controlling for age group, municipality, and proportions of adults who were immunized against influenza. Exposure time was estimated by official municipality population estimates.
  
  
  RESULTS
  We did not observe lower incidence rates of ambulatory visits or hospitalizations for pneumonia among adults during the vaccine period versus the pre-vaccine period. However, pneumonia-related mortality was lower in the vaccine period versus the pre-vaccine period, with an adjusted incidence rate ratio (IRRa) of 0.73 (0.56, 0.94) among adults aged 50-64 years, and 0.55 (0.43, 0.70) among adults aged ≥65 years.
  
  
  CONCLUSIONS
  These early results following introduction of a combined pediatric and adult pneumococcal immunization program in Nicaragua show a probable impact of the program on the reduction of pneumonia-related deaths in older adults, but a less clear impact on the reduction of health facility visits for pneumonia.
authors.affiliation: University of North Carolina School of Medicine, Chapel Hill, NC, USA. Electronic address: sbd@unc.edu.
authors.forename: Sylvia
authors.initials: S
authors.lastname: Becker-Dreps
authors.affiliation: National Autonomous University of Nicaragua, León, Nicaragua.
authors.forename: Erick
authors.initials: E
authors.lastname: Amaya
authors.affiliation: UNC Gillings School of Global Public Health, Chapel Hill, NC, USA.
authors.forename: Lan
authors.initials: L
authors.lastname: Liu
authors.affiliation: Hospital Escuela Oscar Danilo Rosales Argüello (HEODRA), León, Nicaragua.
authors.forename: Julio
authors.initials: J
authors.lastname: Rocha
authors.affiliation: Sistemas Locales de Atención Integral a la Salud, León (SILAIS-León), León, Nicaragua.
authors.forename: Rafaela
authors.initials: R
authors.lastname: Briceño
authors.affiliation: Sistemas Locales de Atención Integral a la Salud, León (SILAIS-León), León, Nicaragua.
authors.forename: Gilberto
authors.initials: G
authors.lastname: Moreno
authors.affiliation: Hospital Escuela Oscar Danilo Rosales Argüello (HEODRA), León, Nicaragua.
authors.forename: Jorge
authors.initials: J
authors.lastname: Alemán
authors.affiliation: UNC Gillings School of Global Public Health, Chapel Hill, NC, USA.
authors.forename: Michael G
authors.initials: MG
authors.lastname: Hudgens
authors.affiliation: Duke University School of Medicine, Durham, NC, USA.
authors.forename: Christopher W
authors.initials: CW
authors.lastname: Woods
authors.affiliation: University of North Carolina School of Medicine, Chapel Hill, NC, USA.
authors.forename: David J
authors.initials: DJ
authors.lastname: Weber
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000553:Ambulatory Care; D005260:Female; D006302:Health Services Research; D006760:Hospitalization; D006801:Humans; D017589:Immunization Programs; D015994:Incidence; D007223:Infant; D008297:Male; D008875:Middle Aged; D009527:Nicaragua / Q000453:epidemiology; D022242:Pneumococcal Vaccines / Q000008:administration & dosage*; D011014:Pneumonia / Q000453:epidemiology* / Q000401:mortality* / Q000517:prevention & control; D016019:Survival Analysis
chemical_list: D022242:Pneumococcal Vaccines
keywords: Adults; Nicaragua; Pneumococcal vaccine; Pneumonia; Streptococcus pneumoniae.