title: Vaccine Induced Herd Immunity for Control of Respiratory Syncytial Virus Disease in a Low-Income Country Setting.
abstract: BACKGROUND
  Respiratory syncytial virus (RSV) is globally ubiquitous, and infection during the first six months of life is a major risk for severe disease and hospital admission; consequently RSV is the most important viral cause of respiratory morbidity and mortality in young children. Development of vaccines for young infants is complicated by the presence of maternal antibodies and immunological immaturity, but vaccines targeted at older children avoid these problems. Vaccine development for young infants has been unsuccessful, but this is not the case for older children (> 6 m). Would vaccinating older children have a significant public health impact? We developed a mathematical model to explore the benefits of a vaccine against RSV.
  
  
  RESULTS
  We have used a deterministic age structured model capturing the key epidemiological characteristics of RSV and performed a statistical maximum-likelihood fit to age-specific hospitalization data from a developing country setting. To explore the effects of vaccination under different mixing assumptions, we included two versions of contact matrices: one from a social contact diary study, and the second a synthesised construction based on demographic data. Vaccination is assumed to elicit an immune response equivalent to primary infection. Our results show that immunisation of young children (5-10 m) is likely to be a highly effective method of protection of infants (<6 m) against hospitalisation. The majority benefit is derived from indirect protection (herd immunity). A full sensitivity and uncertainty analysis using Latin Hypercube Sampling of the parameter space shows that our results are robust to model structure and model parameters.
  
  
  CONCLUSIONS
  This result suggests that vaccinating older infants and children against RSV can have a major public health benefit.
authors.affiliation: School of Mathematics, University of Manchester, Manchester, M13 9PL, United Kingdom.
authors.forename: Timothy M
authors.initials: TM
authors.lastname: Kinyanjui
authors.affiliation: School of Mathematics, University of Manchester, Manchester, M13 9PL, United Kingdom; Department of Mathematics and WIDER, University of Warwick, Coventry, CV4 7AL, United Kingdom.
authors.forename: Thomas A
authors.initials: TA
authors.lastname: House
authors.affiliation: Kenya Medical Research Institute (KEMRI) - Wellcome Trust Research Programme, KEMRI Centre for Geographic Medicine Research - Coast, Kilifi, Kenya.
authors.forename: Moses C
authors.initials: MC
authors.lastname: Kiti
authors.affiliation: Public Health England, Salisbury, United Kingdom.
authors.forename: Patricia A
authors.initials: PA
authors.lastname: Cane
authors.affiliation: Kenya Medical Research Institute (KEMRI) - Wellcome Trust Research Programme, KEMRI Centre for Geographic Medicine Research - Coast, Kilifi, Kenya; School of Life Sciences and WIDER, University of Warwick, Coventry, CV4 7AL, United Kingdom.
authors.forename: David J
authors.initials: DJ
authors.lastname: Nokes
authors.affiliation: Department of Global Health and Development, London School of Hygiene and Tropical Medicine, London, WC1E 7HT, United Kingdom.
authors.forename: Graham F
authors.initials: GF
authors.lastname: Medley
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D002648:Child; D002675:Child, Preschool; D003198:Computer Simulation; D006760:Hospitalization; D006801:Humans; D032521:Immunity, Herd; D007223:Infant; D007630:Kenya / Q000453:epidemiology; D008875:Middle Aged; D008954:Models, Biological; D015233:Models, Statistical; D011203:Poverty; D018357:Respiratory Syncytial Virus Infections / Q000453:epidemiology / Q000276:immunology / Q000517:prevention & control*; D022261:Respiratory Syncytial Virus Vaccines / Q000276:immunology / Q000627:therapeutic use*; D012136:Respiratory Syncytial Viruses / Q000276:immunology*; D014611:Vaccination; D055815:Young Adult
chemical_list: D022261:Respiratory Syncytial Virus Vaccines