RESUMO
BACKGROUND: Chlamydia pneumoniae (C. pneumonia) is an obligate intracellular bacterium and recognized as a risk factor for several diseases such as asthma, atherosclerosis and arthritis. The aim of this study was to determine the seroprevalence of C. pneumonia in healthy subjects in different age groups. METHODS: The serum levels of anti C. pneumonia IgG were measured by using of ELISA. RESULTS: Totally, 630 subjects (164 children and 466 adults) were included into study. The seroprevalence and the mean titer of anti C. pneumonia antibody were 11.3% and 14.48?2.18 RU/mL; at age 510 years, 15% and 17.47 +/- 2.40 RU/mL at age 11-20 years, 21% and 25.15 +/- 4.56 RU/mL at age 21-30 years group, 40% and 53.77 +/- 6.40 RU/mL at age 31-40 years, 94% and 146.41 +/- 8.95 RU/mL at age 41-50 years, 98% and 153.59 +/- 10.38 RU/mL at age 51-60 years, 96% and 138.80 +/- 12.78 RU/mL at age 61-70 years, respectively. The differences of the seroprevalence and the mean titer of anti C. pneumonia antibody between age groups were significant (p<0.0001). The sero-prevalence and the mean titer of anti C. pneumonia antibody were 11.6% and 14.33 +/- 1.49 RU/mL in children and 65.5% and 97.40 +/- 4.46 RU/mL in adults. The seroprevalence and the mean titer of anti C. pneumonia antibody were significantly higher in adults in comparison with those in children (p<0.0001). CONCLUSION: These findings showed that the sero- prevalence and titer of anti C. pneumonia IgG were increased with advanced ages and were higher in adults as compared to children.
Assuntos
Anticorpos Anti-Idiotípicos/sangue , Infecções por Chlamydophila/epidemiologia , Chlamydophila pneumoniae/imunologia , Imunoglobulina G/imunologia , Pneumonia Bacteriana/epidemiologia , Adolescente , Adulto , Idoso , Anticorpos Anti-Idiotípicos/imunologia , Criança , Pré-Escolar , Infecções por Chlamydophila/sangue , Infecções por Chlamydophila/imunologia , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Irã (Geográfico)/epidemiologia , Masculino , Pessoa de Meia-Idade , Pneumonia Bacteriana/sangue , Pneumonia Bacteriana/imunologia , Prevalência , Valores de Referência , Estudos Retrospectivos , Fatores de Risco , Estudos Soroepidemiológicos , Adulto JovemRESUMO
Hepatitis B (HB) vaccine induces protective levels of antibody response (anti-HBs≥10 mIU/mL) in 90-99% of vaccinees. The levels of anti-HBs antibody decline after vaccination. The aim of this study was to evaluate the persistence of anti-HBs antibodies and immunologic memory in healthy adults at 20 years after primary vaccination with recombinant HB vaccine. Blood samples were collected from 300 adults at 20 years after primary HB vaccination and their sera were tested for anti-HBs antibody by ELISA technique. A single booster dose of HB vaccine was administered to a total of 138 subjects, whose anti-HBs antibody titer was <10 mIU/mL. The sera of subjects were re-tested for the anti-HBs antibody levels at 4 weeks after booster vaccination. At 20 years after primary vaccination 37.0% of participants had protective levels of antibody with geometric mean titer (GMT) of 55.44±77.01 mIU/mL. After booster vaccination, 97.1% of vaccinees developed protective levels of antibody and the GMT rose from 2.35±6.49 mIU/mL to 176.28±161.78 mIU/mL. 125/138 (90.6%) of re-vaccinated subjects also showed an anamnestic response to booster vaccination. At 20 years after primary vaccination with HB vaccine, low proportion of the subjects had protective levels of antibody. However, the majority of the re-vaccinated subjects developed protective levels of anti-HBs and showed an anamnestic response after booster vaccination. Additional follow-up studies are necessary to determine the duration of immunological memory.
