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Because of the continued importance of correct condom-use in controlling the HIV epidemic and the limited availability of tools for assessing correct condom-use, methods for assessing condom-application skills, especially when direct observation is not feasible, are needed. Accordingly, in the context of a high-risk population (The Bahamas) for HIV, a 17-item scale--the Condom-use Skills Checklist (CUSC)--was developed for use among young adolescents and adults. The rationale and approach to developing the scale and some measures of internal consistency, construct validity, and criterion-related validity have been described. It is concluded that the scale offers a reasonable alternative to direct observation among older subjects and that further development may make it more useful among pre-adolescents.

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The prevalence of antibodies to hepatitis A and B virus was assessed in 3,653 subjects across four regions of Brazil. The anti-HAV and anti-HBc seroprevalence were 64.7% and 7.9%, respectively. The highest anti-HAV (92.8%) and anti-HBc (21.4%) rates were seen in the Northern region. In other regions, anti-HAV seroprevalence over 90% was only reached in the more elderly, indicating an intermediate endemicity and a significantly higher anti-HAV prevalence was seen in the low socioeconomic group between 1-30 years. With respect to anti-HBc seroprevalence an increase was seen in adolescents and there was a significantly higher anti-HBc prevalence in the lower socioeconomic group between 1-20 years. A 3.1% anti-HBc prevalence was seen in one-year-old infants, suggesting a vertical transmission. The major findings of this study indicate that the pre-adolescent and adolescent population in some Brazilian cities are at greatest risk from both hepatitis A and B infection, but for different reasons.

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A doença causada pelo virus da hepatite A (VHA) costuma ser considerada como benigna, afetando principalmente os pré-escolares. Contudo, nesta revisäo se discutem os vários grupos da populaçäo em geral, nos quais a infecçäo pelo VHA pode apresentar consequências mais graves. Em consequência da alteraçäo epidemiológica verificada na América Latina, um número cada vez maior de adolescentes e adultos jovens se mantêm suscetíveis à infecçäo pelo VHA. A infecçäo por esse vírus, neste grupo etário, irá representar grave impacto no futuro, ausência prolongada ao trabalho e/ou escola e custos maiores para os sistemas locais de saúde. Em estudos recentes na Argentina e Chile, o VHA foi, também, o agente etiológico mais prevalente nos casos de insuficiência hepática fulminante em pré-escolares. A hepatite A aguda em pacientes com doença hepática crônica subjacente, especialmente hepatite C crônica, tem sido associada à insuficiência hepática grave ou fulminante. A prevençäo da hepatite A através da vacinaçäo parece ser o meio mais potente de se conter o VHA. As vacinas inativadas contra a hepatite A comprovaram ser seguras, altamente imunogênicas e indutoras de proteçäo duradoura contra infecçöes pelo VHA

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OJECTIVES: Varicella has more serious consequences in adolescents and adults. Recent reports from Europe and Asia show an increasing number of adolescents and young adults being seronegative. As there is only limited data on varicella zoster virus (VZV) seroprevalence in Brazil and to facilitate the strategy for varicella vaccination we conducted a VZV seroprevalence study in Brazil. METHODS: This population-based, cross sectional seroepidemiology study was performed in 4 different regions of Brazil. The studied population was stratified according to gender, age and socioeconomic status. VZV IgG antibodies were analyzed by ELISA. RESULTS: 3,879 subjects aged 1-40 years were included into the study. The overall anti-VZV seropositivity rate across all age groups and centers in Brazil was 85.4%. There was a strong age relationship. Especially in the South East and South seroprevalence was low in the age group 1-5 years (44.5% and 57.8%, respectively) while in the North the rate was 88.9%. Overall, Varicella infection was independent of the socioeconomic level, but in the youngest age groups (1-10 years) seroprevalence rates were significantly lower in the high/medium socioeconomic class for most regions. Clinical history of chickenpox correlates well with anti- VZV seropositivity with a predictive value of 95.1% CONCLUSIONS: In preadolescence a substantial proportion of the Brazilian population is susceptible to Varicella infection, and a considerable part of the adolescents and young adults remain VZVseronegative and are thus also at risk.

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OBJECTIVES: The primary objective was to assess the nature and incidence of adverse events after a fourth dose of a tricomponent acellular pertussis-diphtheriatetanus vaccine given in the second year of life after primary vaccination with the same vaccine at 3, 4, and 5 months of age. A secondary objective was to analyze the immunogeniecity of the booster vaccination. DESIGN: Of the 5361 children enrolled (aged 14 to 28 months), adverse reactions were specifically solicited from the first 1863 enrollees for the first 4 days after vaccination and then were unsolicited for the remainder of the 4 weeks of follow-up (group 1). In the next 3498 subjects, safety and reactogenicify were entirely unsolicited for this 4-week period (group 2). Immunogenicity was analyzed by means of prebooster and postbooster serum antibody titers for all vaccine components in a random subgroup of 197 children from group 1. RESULTS: Soliciting symptoms elicited reports of at least one symptom in 1314 of 1809 children in group 1 (72.6%), including 993 (54.9%) with local and 885 (48.9%) with general symptoms during the first 4 days after vaccination. When symptoms were gathered in an unsolicited fashion, only 580 of 3498 children in group 2 (16.6%) had a reported symptom during this time, consisting of 344 (9.8%) local and 319 (9.1%) general symptoms, respectively. An unsolicited symptom, areactive edematous swelling of the whole thigh, occurred in 62 children (1.1%), with 45 and 17 reports in groups 1 and 2, respectively. The vast majority of all reported symptoms were mild to moderate, and all children recovered without sequelae. Fourteen serious adverse events were reported, but none was considered to be related to the vaccination. Immunogenicity analysis showed a vaccine response to pertussis toxin in 99.5% of subjects, to filamentous hemagglutinin in 98.5%, and to pertactin (69 kd outer membrane protein) in 99%. All subjects had postvaccination antibody titers of 0.1 IU/ml or greater against diphtheria and tetanus toxoids.

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OBJECTIVES: To assess the safety and tolerability of 12 lots of SmithKline Beecham Biologicals' diphtheria-tetanus-tricomponent acellular pertussis vaccine (DTaP) in a large cohort of 22,000 vaccinees, with detailed analyses of reactivity, immunogenicity, and immune response to pertussis toxin in subsets. METHODS: In a prospective, double-blind, multicenter trial in Germany, 22,505 healthy infants received three vaccinations of DTaP at age 3, 4, and 5 months. Serious adverse events were followed for 1 month after each vaccination, and neurologic events for 1 year or longer. Serum IgG antibodies were assayed before vaccination and 1 month after vaccination. RESULTS: After 67,000 doses, 153 serious adverse events (0.23%) were reported, 8 considered possibly related, and 5 related to vaccination, including 1 hypotonic-hyporesponsive episode. Incidence rates of sudden infant death syndrome (7; 0.01%) or acute neurologic events (20; 0.030%) were no higher than expected and not considered to be related to vaccination. Redness and swelling of 20 mm or greater occurred after 44 (0.6%) and 40 (0.6%) of the 7270 doses, respectively, and high fever (> 39.5 degrees C) in 6 (0.08%) subjects within 48 hours of vaccination. In the immunogenicity analysis of 580 infants, 98% responded to pertussis toxin, 96% to filamentous hemagglutinin, and 98% to pertactin. In an additional 5712 infants, the response rate to pertussis toxin was 99%. CONCLUSIONS: In a large cohort of 22,505 infants vaccinated, SmithKline Beecham Biologicals' tricomponent DTaP vaccine was shown to be safe, well-tolerated, and immunogenic for all component antigens.

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