Search

Background: Prenatal tests are important for prevention of vertical transmission of various infectious agents. The objective of this study was to describe the prevalence of human immunodeficiency virus (HIV), human T-lymphotropic virus (HTLV), hepatitis B virus (HBV), cytomegalovirus (CMV), rubella virus and vaccination coverage against HBV in pregnant adolescents who received care in the city of Belém, Pará, Brazil., Methods: A cross-sectional study was performed with 324 pregnant adolescents from 2009 to 2010. After the interview and blood collection, the patients were screened for antibodies and/or antigens against HIV-1/2, HTLV-1/2, CMV, rubella virus and HBV. The epidemiological variables were demonstrated using descriptive statistics with the G, χ 2 and Fisher exact tests., Results: The mean age of the participants was 15.8 years, and the majority (65.4%) had less than 6 years of education. The mean age at first intercourse was 14.4 years, and 60.8% reported having a partner aged between 12 and 14 years. The prevalence of HIV infection was 0.3%, and of HTLV infection was 0.6%. Regarding HBV, 0.6% of the participants had acute infection, 9.9% had a previous infection, 16.7% had vaccine immunity and 72.8% were susceptible to infection. The presence of anti-HBs was greater in adolescent between 12 and 14 years old (28.8%) while the anti-HBc was greater in adolescent between 15 and 18 years old (10.3%). Most of the adolescents presented the IgG antibody to CMV (96.3%) and rubella (92.3%). None of the participants had acute rubella infection, and 2.2% had anti-CMV IgM., Conclusions: This study is the first report of the seroepidemiology of infectious agents in a population of pregnant adolescents in the Northern region of Brazil. Most of the adolescents had low levels of education, were susceptible to HBV infection and had IgG antibodies to CMV and rubella virus. The prevalence of HBV, HIV and HTLV was similar to that reported in other regions of Brazil. However, the presence of these agents in this younger population reinforces the need for good prenatal follow-up and more comprehensive vaccination campaigns against HBV due to the large number of women susceptible to the virus.

Purpose: To ascertain the seroprevalence of human immunodeficiency virus (HIV), hepatitis B (HBV), toxoplasmosis and rubella infections in pregnant women in northwestern Paraná., Methods: We conducted a retrospective study based on the results of serological screening during prenatal care of 1,534 patients during the first half of 2010. We included only results from the first prenatal exam and with a simultaneous search for IgG and IgM antibodies to rubella and toxoplasmosis. Serology was performed by microparticle enzyme immunoassay (MEIA). Data were analyzed statistically by the χ² test, with the level of significance set at 5%., Results: HIV positivity was 0.3%, positivity of HBV serology (HbsAg) was 0.5%, reactivity to IgM antibodies to Toxoplasma gondii was 1.1%, and reactivity to IgG antibodies was 59.0%. For rubella, no patient was positive for IgM, and IgG reactivity was 99.6%. Data analysis showed no statistical association between seroprevalence and patient age, except for the frequency of anti-T. gondii IgG, which was higher in the 30 to 44 year age group., Conclusion: The prevalence of these infectious diseases in pregnant women from northwestern Paraná is comparable to that observed in other regions of Brazil.

Background: Serologic immunity studies are necessary to evaluate immunization policies for rubella control and prevention of congenital rubella syndrome (CRS), and serologic data from regular testing for clinical follow-up can be used to complement surveillance information., Methods: To assess immunity to rubella after an immunization campaign in 12-29-year-old girls and women, we retrospectively reviewed immunoglobulin (Ig) G tests performed from 2000 to 2003 in 9610 serum samples from pregnant subjects in Niterói, Rio de Janeiro, Brazil. Serologic tests for rubella were performed using commercial enzyme immunoassays., Results: Rubella IgG were positive in 83.9% of serum samples collected before the campaign and in 92.5% after the campaign. The proportion of seropositive subjects was inversely related to age (P < .001). The proportion of immune girls or women aged 12-29 years, targeted by the campaign, was significantly increased after the campaign, whereas women aged ≥ 30 years, not targeted by the campaign, had no change in serologic immunity. Geometric mean titers for rubella IgG were significantly higher among pregnant girls and women after the vaccination campaign., Conclusions: The convenience sample provided evidence of increased population immunity among the girls and women targeted by the campaign, but with a coverage of only 83% there remains a significant population at risk for rubella and thus congenital rubella syndrome.

Objective: We evaluated the seroprevalence for measles, mumps, and rubella in school-age children (6-12 years old) before and after the administration of three triple combined viral vaccines., Methods: In two municipal schools of Rio Grande do Sul, Brazil, 692 blood samples were collected before vaccination and 636 samples 21 to 30 days after vaccination during 1996. IgG antibody seropositivity was investigated by enzyme-linked immunosorbent assay (measles and mumps with Enzygnost [Behring, Marburg, Germany]; rubella with Rubenostika [Organon Teknica, Boxtel, the Netherlands]). The vaccines compared were: A: E-Zagreb, L-Zagreb, and Wistar RA 27/3 (Tresivac); B: Moraten, J-Lynn, and Wistar RA 27/3 (M-M-R II); and C: Schwarz, Urabe AM-9, and Wistar RA 27/3 (Trimovax)., Results: Before vaccination, 79.2% [95% confidence interval (CI)=76.0%-82.2%] of the samples were positive for measles, 69.4% (95% CI=65.8%-72.8%) for mumps, and 55.4% (95% CI=51.6%-59.2%) for rubella. After vaccination with the A, B, and C vaccines, seropositivity was 100.0%, 99.5%, and 100.0%, respectively for measles; 99.5%, 94.5%, and 92.0% for mumps; and 92.6%, 91.3%, and 88.6% for rubella., Conclusions: About one-fifth (20.8%) of the schoolchildren who could have been vaccinated against measles at age 9 months had levels of antibodies insufficient for protection. In the sample of schoolchildren without previous vaccination against mumps and rubella, high proportions of susceptible levels were found. All vaccines were immunogenic, but vaccine A yielded a seroconversion rate of 99.5% for the mumps component, which was significantly higher than the other two vaccines (P<0.01).

We collected acute-phase and convalescent-phase serum samples from Brazilian patients who presented with exanthem of unknown origin and evaluated these samples by means of an immunoblot assay for seroconversion to human herpesvirus 6 (HIV-6) or human herpesvirus 7 (HIV-7). Measles or rubella had been clinically diagnosed in all these patients, but their sera were negative for antibodies to both measles virus and rubella virus. Twenty percent of the patients clearly seroconverted to HHV-6 after manifestation of the exanthem, and 8% seroconverted to HHV-7. All seroconversions to HHV-6 occurred in children aged < or = 5 years; a 41% frequency of seroconversion to HHV-6 was noted among children between 3 months and 23 months of age, whereas seroconversions to HHV-7 were detected during infancy and through adulthood. Our data indicate that primary infections due to HHV-6 or HHV-7 can be misdiagnosed as measles or rubella.

The prevalence of rubella antibodies was evaluated through a random seroepidemiological survey in 1400 blood samples of 2-14 year old children and in 329 samples of umbilical cord serum. Rubella IgG antibodies were detected by ELISA, and the sera were collected in 1987, five years before the mass vaccination campaign with measles-mumps-rubella vaccine carried out in the city of São Paulo in 1992. A significant increase in prevalence of rubella infection was observed after 6 years of age, and 77% of the individuals aged from 15 to 19 years had detectable rubella antibodies. However, the seroprevalence rose to 90.5% (171/189) in cord serum samples from children whose mothers were 20 to 29 years old, and reached 95.6% in newborns of mothers who were 30 to 34 years old, indicating that a large number of women are infected during childbearing years. This study confirms that rubella infection represents an important Public Health problem in São Paulo city. The data on the seroprevalence of rubella antibodies before the mass vaccination campaign reflects the baseline immunological status of this population before any intervention and should be used to design an adequate vaccination strategy and to assess the seroepidemiological impact of this intervention.