title: Evaluation of Haemophilus influenzae type b carrier status among children 10 years after the introduction of Hib vaccine in Brazil.
abstract: The aim of the present study was to assess the prevalence of Haemophilus influenzae type b (Hib) nasopharyngeal (NP) colonisation among healthy children where Hib vaccination using a 3p+0 dosing schedule has been routinely administered for 10 years with sustained coverage (> 90%). NP swabs were collected from 2,558 children who had received the Hib vaccine, of whom 1,379 were 12-< 24 months (m) old and 1,179 were 48-< 60 m old. Hi strains were identified by molecular methods. Hi carriage prevalence was 45.1% (1,153/2,558) and the prevalence in the 12-< 24 m and 48-< 60 m age groups were 37.5% (517/1,379) and 53.9% (636/1,179), respectively. Hib was identified in 0.6% (16/2,558) of all children in the study, being 0.8% (11/1,379) and 0.4% (5/1,179) among the 12-< 24 m and 48-< 60 m age groups, respectively. The nonencapsulate Hi colonisation was 43% (n = 1,099) and was significantly more frequent at 48-< 60 m of age (51.6%, n = 608) compared with that at 12-< 24 m of age (35.6%, n = 491). The overall resistance rates to ampicillin and chloramphenicol were 16.5% and 3.7%, respectively; the co-resistance was detected in 2.6%. Our findings showed that the Hib carrier rate in healthy children under five years was very low after 10 years of the introduction of the Hib vaccine.
authors.affiliation: Centro de Bacteriologia, Instituto Adolfo Lutz, Secretaria de Estado da Saúde de São Paulo, São Paulo, SP, Brasil.
authors.forename: Rosemeire Cobo
authors.initials: RC
authors.lastname: Zanella
authors.affiliation: Centro de Bacteriologia, Instituto Adolfo Lutz, Secretaria de Estado da Saúde de São Paulo, São Paulo, SP, Brasil.
authors.forename: Maria Cristina de Cunto
authors.initials: MC
authors.lastname: Brandileone
authors.affiliation: Instituto de Patologia Tropical e Saúde Pública, Universidade Federal de Goiás, Goiânia, GO, Brasil.
authors.forename: Ana Lúcia
authors.initials: AL
authors.lastname: Andrade
authors.affiliation: Centro de Bacteriologia, Instituto Adolfo Lutz, Secretaria de Estado da Saúde de São Paulo, São Paulo, SP, Brasil.
authors.forename: Cinthya Terumi
authors.initials: CT
authors.lastname: Ogassavara
authors.affiliation: Centro de Bacteriologia, Instituto Adolfo Lutz, Secretaria de Estado da Saúde de São Paulo, São Paulo, SP, Brasil.
authors.forename: Cleiton Eduardo
authors.initials: CE
authors.lastname: Fiório
authors.affiliation: Centro de Bacteriologia, Instituto Adolfo Lutz, Secretaria de Estado da Saúde de São Paulo, São Paulo, SP, Brasil.
authors.forename: Angela Pires
authors.initials: AP
authors.lastname: Brandão
authors.affiliation: Centro de Bacteriologia, Instituto Adolfo Lutz, Secretaria de Estado da Saúde de São Paulo, São Paulo, SP, Brasil.
authors.forename: Samanta Cristine Grassi
authors.initials: SC
authors.lastname: Almeida
authors.affiliation: Centro de Bacteriologia, Instituto Adolfo Lutz, Secretaria de Estado da Saúde de São Paulo, São Paulo, SP, Brasil.
authors.forename: Ana Paula Silva
authors.initials: AP
authors.lastname: Lemos
authors.affiliation: Centro de Bacteriologia, Instituto Adolfo Lutz, Secretaria de Estado da Saúde de São Paulo, São Paulo, SP, Brasil.
authors.forename: Maria Cecília
authors.initials: MC
authors.lastname: Gorla
authors.affiliation: Divisão de Doenças de Transmissão Respiratória, Centro de Vigilância Epidemiológica, Secretaria de Estado da Saúde de São Paulo, São Paulo, SP, Brasil.
authors.forename: Telma Regina
authors.initials: TR
authors.lastname: Carvalhanas
authors.affiliation: Divisão de Doenças de Transmissão Respiratória, Centro de Vigilância Epidemiológica, Secretaria de Estado da Saúde de São Paulo, São Paulo, SP, Brasil.
authors.forename: Helena
authors.initials: H
authors.lastname: Sato
authors.affiliation: Divisão de Doenças de Transmissão Respiratória, Centro de Vigilância Epidemiológica, Secretaria de Estado da Saúde de São Paulo, São Paulo, SP, Brasil.
authors.forename: Bernadete
authors.initials: B
authors.lastname: Liphaus
authors.affiliation: Centro de Controle de Doenças, Secretaria Municipal da Saúde, São Paulo, SP, Brasil.
authors.forename: Maria Lígia
authors.initials: ML
authors.lastname: Nerger
authors.affiliation: Centro de Controle de Doenças, Secretaria Municipal da Saúde, São Paulo, SP, Brasil.
authors.forename: Monica
authors.initials: M
authors.lastname: Conde
authors.affiliation: Divisão de Doenças de Transmissão Respiratória, Centro de Vigilância Epidemiológica, Secretaria de Estado da Saúde de São Paulo, São Paulo, SP, Brasil.
authors.forename: Ana Freitas
authors.initials: AF
authors.lastname: Ribeiro
mesh_terms: D000668:Ampicillin Resistance / Q000276:immunology; D016667:Bacterial Capsules / Q000276:immunology; D001938:Brazil / Q000453:epidemiology; D002353:Carrier State / Q000276:immunology* / Q000382:microbiology; D002675:Child, Preschool; D002702:Chloramphenicol Resistance / Q000276:immunology; D003430:Cross-Sectional Studies; D006192:Haemophilus Infections / Q000453:epidemiology / Q000517:prevention & control*; D018073:Haemophilus Vaccines / Q000627:therapeutic use*; D019741:Haemophilus influenzae type b / Q000145:classification / Q000276:immunology*; D006801:Humans; D007115:Immunization Schedule; D007223:Infant; D032541:Mass Vaccination; D008826:Microbial Sensitivity Tests; D009305:Nasopharynx / Q000382:microbiology*; D016133:Polymerase Chain Reaction; D015995:Prevalence; D011795:Surveys and Questionnaires
chemical_list: D018073:Haemophilus Vaccines