title: Direct effect of 10-valent conjugate pneumococcal vaccination on pneumococcal carriage in children Brazil.
abstract: BACKGROUND
  10-valent conjugate pneumococcal vaccine/PCV10 was introduced in the Brazilian National Immunization Program along the year of 2010. We assessed the direct effectiveness of PCV10 vaccination in preventing nasopharyngeal/NP pneumococcal carriage in infants.
  
  
  METHODS
  A cross-sectional population-based household survey was conducted in Goiania Brazil, from December/2010-February/2011 targeting children aged 7-11 m and 15-18 m. Participants were selected using a systematic sampling. NP swabs, demographic data, and vaccination status were collected from 1,287 children during home visits. Main outcome and exposure of interest were PCV10 vaccine-type carriage and dosing schedules (3p+0, 2p+0, and one catch-up dose), respectively. Pneumococcal carriage was defined by a positive culture and serotyping was performed by Quellung reaction. Rate ratio/RR was calculated as the ratio between the prevalence of vaccine-types carriage in children exposed to different schedules and unvaccinated for PCV10. Adjusted RR was estimated using Poisson regression. PCV10 effectiveness/VE on vaccine-type carriage was calculated as 1-RR*100.
  
  
  RESULTS
  The prevalence of pneumococcal carriage was 41.0% (95%CI: 38.4-43.7). Serotypes covered by PCV10 and PCV13 were 35.2% and 53.0%, respectively. Vaccine serotypes 6B (11.6%), 23F (7.8%), 14 (6.8%), and 19F (6.6%) were the most frequently observed. After adjusted for confounders, children who had received 2p+0 or 3p+0 dosing schedule presented a significant reduction in pneumococcal vaccine-type carriage, with PCV10 VE equal to 35.9% (95%CI: 4.2-57.1; p = 0.030) and 44.0% (95%CI: 14.-63.5; p = 0.008), respectively, when compared with unvaccinated children. For children who received one catch-up dose, no significant VE was detected (p = 0.905).
  
  
  CONCLUSIONS
  PCV10 was associated with high protection against vaccine-type carriage with 2p+0 and 3p+0 doses for children vaccinated before the second semester of life. The continuous evaluation of carriage serotypes distribution is likely to be useful for evaluating the long-term effectiveness and impact of pneumococcal vaccination on serotypes reduction.
authors.affiliation: Institute of Tropical Pathology and Public Health, Federal University of Goias, Goiania, Brazil.
authors.forename: Ana Lucia
authors.initials: AL
authors.lastname: Andrade
authors.affiliation: Institute of Tropical Pathology and Public Health, Federal University of Goias, Goiania, Brazil; Epidemiology Branch, Secretariat of Health of Municipality of Goiania, Goias, Brazil.
authors.forename: Yves Mauro
authors.initials: YM
authors.lastname: Ternes
authors.affiliation: Pontifical Catholic University of Goias, Goiania, Brazil.
authors.forename: Maria Aparecida
authors.initials: MA
authors.lastname: Vieira
authors.affiliation: Institute of Tropical Pathology and Public Health, Federal University of Goias, Goiania, Brazil; Laboratory of Bacteriology, Federal University of Goias, Goiania, Brazil.
authors.forename: Weslley Garcia
authors.initials: WG
authors.lastname: Moreira
authors.affiliation: Laboratory of Bacteriology, Federal University of Goias, Goiania, Brazil.
authors.forename: Juliana
authors.initials: J
authors.lastname: Lamaro-Cardoso
authors.affiliation: Laboratory of Bacteriology, Federal University of Goias, Goiania, Brazil.
authors.forename: André
authors.initials: A
authors.lastname: Kipnis
authors.affiliation: Department of Epidemiology, School of Public Health, University of Sao Paulo, Sao Paulo, Brazil.
authors.forename: Maria Regina
authors.initials: MR
authors.lastname: Cardoso
authors.affiliation: Adolfo Lutz Institute, Sao Paulo, Brazil.
authors.forename: Maria Cristina
authors.initials: MC
authors.lastname: Brandileone
authors.affiliation: Respiratory Diseases Branch, Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America.
authors.forename: Iaci
authors.initials: I
authors.lastname: Moura
authors.affiliation: Respiratory Diseases Branch, Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America.
authors.forename: Fabiana C
authors.initials: FC
authors.lastname: Pimenta
authors.affiliation: Respiratory Diseases Branch, Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America.
authors.forename: Maria
authors.initials: M
authors.lastname: da Gloria Carvalho
authors.affiliation: Institute of Tropical Pathology and Public Health, Federal University of Goias, Goiania, Brazil.
authors.forename: Fabricia Oliveira
authors.initials: FO
authors.lastname: Saraiva
authors.affiliation: Institute of Tropical Pathology and Public Health, Federal University of Goias, Goiania, Brazil.
authors.forename: Cristiana Maria
authors.initials: CM
authors.lastname: Toscano
authors.affiliation: Faculty of Nursing, Federal University of Goias, Goiania, Brazil.
authors.forename: Ruth
authors.initials: R
authors.lastname: Minamisava
mesh_terms: D017677:Age Distribution; D001938:Brazil; D002353:Carrier State / Q000276:immunology* / Q000382:microbiology*; D002648:Child; D004306:Dose-Response Relationship, Immunologic; D006801:Humans; D007223:Infant; D009305:Nasopharynx / Q000276:immunology / Q000382:microbiology; D011008:Pneumococcal Infections / Q000276:immunology* / Q000382:microbiology / Q000517:prevention & control*; D022242:Pneumococcal Vaccines / Q000276:immunology*; D014611:Vaccination
chemical_list: C586648:10-valent pneumococcal conjugate vaccine; D022242:Pneumococcal Vaccines