RESUMO
The immunogenicity of two hepatitis B vaccines was compared in 8-10-year-old children immunized in a school program. One year apart, 1129 children received Engerix-B 10 microg vaccine (EB), and 1126 received Recombivax-HB 2.5 microg (RB), following the 0, 1, 6 schedule. Blood samples were collected one month after the third dose. Anti-Hbs were measured by commercial radioimmunoassay. In the EB group, 99.1% of the children seroconverted (>/=2 IU/l) compared to 99.7% in the RHB group (p=0.09). The seroprotection rate (>/=10 IU/l) was similar for both groups: 98.9% in the EB group and 99.2% in the RB group (p=0.66). However, GMCs of anti-HBs were higher in children given EB compared to those given RB (7307 vs. 3800 mIU/ml, p<0.0001). This study showed that both vaccines were highly immunogenic, in the course of a regular field immunization program. However, the difference observed in the antibody levels attained according to the vaccine may play a role in the long-term protection of these children.
Assuntos
Vacinas contra Hepatite B/imunologia , Vacinas Sintéticas/imunologia , Criança , Feminino , Anticorpos Anti-Hepatite B/sangue , Humanos , Imunização , MasculinoAssuntos
Imunização/estatística & dados numéricos , Vacinação/estatística & dados numéricos , Adolescente , Adulto , Idoso , Atitude Frente a Saúde , Vacinas Bacterianas , Estudos Transversais , Toxoide Diftérico , Feminino , Conhecimentos, Atitudes e Prática em Saúde , Vacinas contra Hepatite B , Humanos , Vacinas contra Influenza , Masculino , Pessoa de Meia-Idade , Quebeque/epidemiologia , Streptococcus pneumoniae/imunologia , Toxoide TetânicoRESUMO
OBJECTIVES: 1) to identify potential risk factors for measles and 2) to assess the efficacy of the measles vaccine. METHODS: Cases of measles reported from primary and secondary schools in Montreal during the 1989 epidemic were compared with classroom and sibling controls with respect to age at vaccination against measles, time since vaccination, type of vaccination, type of providers and age of the mother. RESULTS: Subjects vaccinated at 12 months had an OR of 3.9 (CI 95%: 2.1 to 7.0) of contracting measles when compared with subjects vaccinated at 15 months or later. Vaccination at age 13 or 14 months was not associated with an increased risk. Subjects vaccinated before June 1979 had an OR of 5.8 (CI 95%: 2.8 to 12.1) of developing measles compared with subjects vaccinated after June 1980. Vaccine efficacy was 96.1%. DISCUSSION: In highly vaccinated populations, vaccination at 12 months and vaccination before 1980 are probably two reasons why outbreaks still occur. The two-dose schedule could reduce the proportion of vaccinated persons who remain susceptible.