title: Long-term complications and risk of other serious infections following invasive Haemophilus influenzae serotype b disease in vaccinated children.
abstract: This study describes the long-term complications in children with Haemophilus influenzae serotype b (Hib) vaccine failure and to determine their risk of other serious infections. The families of 323 children with invasive Hib disease after appropriate vaccination (i.e. vaccine failure) were contacted to complete a questionnaire relating to their health and 260 (80.5%) completed the questionnaire. Of the 124 children with meningitis, 18.5% reported serious long-term sequelae and a further 12.1% of parents attributed other problems to Hib meningitis. Overall, 14% (32/231 cases) of otherwise healthy children and 59% (17/29 cases) of children with an underlying condition developed at least one other serious infection requiring hospital admission. In a Poisson regression model, the risk of another serious infection was independently associated with the presence of an underlying medical condition (incidence risk ratio (IRR) 7.6, 95% CI 4.8-12.1; p<0.0001), both parents having had a serious infection (IRR 4.1, 95% CI 1.6-10.3; p=0.003), requirement of more than two antibiotic courses per year (IRR 2.3, 95% CI 1.4-3.6; p=0.001) and the presence of a long-term complication after Hib infection (IRR 1.8, 95% CI 1.1-3.1; p=0.03). Thus, rates of long-term sequelae in children with vaccine failure who developed Hib meningitis are similar to those in unvaccinated children in the pre-vaccine era. One in seven otherwise healthy children (14%) with Hib vaccine failure will go on to suffer another serious infection requiring hospital admission in childhood, which is higher than would be expected for the UK paediatric population.
authors.affiliation: Academic Unit of Paediatrics, Barts and The London School of Medicine and Dentistry, London, United Kingdom. Electronic address: shamez.ladhani@hpa.org.uk.
authors.forename: Shamez
authors.initials: S
authors.lastname: Ladhani
authors.affiliation: Vaccine Institute and Division of Child Health, St George's, University of London, United Kingdom.
authors.forename: Paul T
authors.initials: PT
authors.lastname: Heath
authors.affiliation: Department of Paediatrics, Central Middlesex Hospital, London, United Kingdom.
authors.forename: Rashna J
authors.initials: RJ
authors.lastname: Aibara
authors.affiliation: Centre for Infections, Health Protection Agency, London, United Kingdom.
authors.forename: Mary E
authors.initials: ME
authors.lastname: Ramsay
authors.affiliation: Centre for Infections, Health Protection Agency, London, United Kingdom.
authors.forename: Mary P E
authors.initials: MPE
authors.lastname: Slack
authors.affiliation: Infectious Diseases Unit, Genome Institute of Singapore, Republic of Singapore.
authors.forename: Martin L
authors.initials: ML
authors.lastname: Hibberd
authors.affiliation: Oxford Vaccine Group, Department of Paediatrics, University of Oxford, United Kingdom.
authors.forename: Andrew J
authors.initials: AJ
authors.lastname: Pollard
authors.affiliation: Oxford Vaccine Group, Department of Paediatrics, University of Oxford, United Kingdom.
authors.forename: E Richard
authors.initials: ER
authors.lastname: Moxon
authors.affiliation: Academic Unit of Paediatrics, Barts and The London School of Medicine and Dentistry, London, United Kingdom; National Centre for Immunisation Research & Surveillance, University of Sydney, Australia.
authors.forename: Robert
authors.initials: R
authors.lastname: Booy
mesh_terms: D000293:Adolescent; D016667:Bacterial Capsules / Q000008:administration & dosage* / Q000276:immunology*; D002648:Child; D002675:Child, Preschool; D005260:Female; D006192:Haemophilus Infections / Q000150:complications* / Q000382:microbiology*; D018073:Haemophilus Vaccines / Q000008:administration & dosage* / Q000276:immunology*; D019741:Haemophilus influenzae type b / Q000302:isolation & purification*; D006801:Humans; D007223:Infant; D008297:Male; D012307:Risk Factors; D011795:Surveys and Questionnaires; D017211:Treatment Failure; D006113:United Kingdom
chemical_list: D018073:Haemophilus Vaccines; C044237:Haemophilus influenzae type b polysaccharide vaccine