title: Optimizing strategies for meningococcal C disease vaccination in Valencia (Spain).
abstract: BACKGROUND
  Meningococcal C (MenC) conjugate vaccines have controlled invasive diseases associated with this serogroup in countries where they are included in National Immunization Programs and also in an extensive catch-up program involving subjects up to 20 years of age. Catch-up was important, not only because it prevented disease in adolescents and young adults at risk, but also because it decreased transmission of the bacteria, since it was in this age group where the organism was circulating. Our objective is to develop a new vaccination schedule to achieve maximum seroprotection in these groups.
  
  
  METHODS
  A recent study has provided detailed age-structured information on the seroprotection levels against MenC in Valencia (Spain), where vaccination is routinely scheduled at 2 months and 6 months, with a booster dose at 18 months of age. A complementary catch-up campaign was also carried out in n for children from 12 months to 19 years of age. Statistical analyses of these data have provided an accurate picture on the evolution of seroprotection in the last few years.
  
  
  RESULTS
  An agent-based model has been developed to study the future evolution of the seroprotection histogram. We have shown that the optimum strategy for achieving high protection levels in all infants, toddlers and adolescents is a change to a 2 months, 12 months and 12 years of age vaccination pattern. If the new schedule were implemented in January 2014, high-risk subjects between 15-19 years of age would have very low seroprotection for the next 6 years, thereby threatening the program.
  
  
  CONCLUSIONS
  High protection levels and a low incidence of meningococcal C disease can be achieved in the future by means of a cost-free change in vaccination program. However, we recommend a new catch-up program simultaneous to the change in regular vaccination program.
authors.forename: Lina
authors.initials: L
authors.lastname: Pérez-Breva
authors.forename: Rafael J
authors.initials: RJ
authors.lastname: Villanueva
authors.forename: Javier
authors.initials: J
authors.lastname: Villanueva-Oller
authors.affiliation: Instituto de Matemática Multidisciplinar, Edificio 8G 2° Floor, Universitat Politècnica de Valéncia, Camino de Vera s/n, 46022 Valencia, Spain. luiacrod@imm.upv.es.
authors.forename: Luis
authors.initials: L
authors.lastname: Acedo
authors.forename: Francisco
authors.initials: F
authors.lastname: Santonja
authors.forename: José A
authors.initials: JA
authors.lastname: Moraño
authors.forename: Raquel
authors.initials: R
authors.lastname: Abad
authors.forename: Julio A
authors.initials: JA
authors.lastname: Vázquez
authors.forename: Javier
authors.initials: J
authors.lastname: Díez-Domingo
mesh_terms: D000293:Adolescent; D000328:Adult; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D017589:Immunization Programs; D008297:Male; D008589:Meningococcal Infections / Q000517:prevention & control*; D022401:Meningococcal Vaccines / Q000008:administration & dosage*; D008875:Middle Aged; D013030:Spain; D014611:Vaccination / Q000379:methods; D055815:Young Adult
chemical_list: D022401:Meningococcal Vaccines; C410218:serogroup C meningococcal conjugate vaccine