Immunogenicity and efficacy of a killed hepatitis A vaccine in day care center children.

The objective of this study was to characterize the immune response of children after the use of two different vaccine doses and to evaluate whether vaccination benefits children attending day care centers in areas with high anti-HAV seroprevalence. The study was conducted in a day care center with a stable population in São Paulo, Brazil. Two groups of 20 children, all seronegative for hepatitis A antibodies, were assigned randomly to receive three times 0.5 and 1.0 ml of the vaccine, the second and third dose 1 and 6 months after the first dose, respectively. There were 27 children in the control group. All children in both vaccinated groups had protective levels of antibodies in the serum after two inoculations, and serious adverse reactions were not observed. In the eighth month of follow-up, a hepatitis A outbreak occurred in the day care center. Five children in the control group had high titers of IgM class anti-HAV, four with clinical manifestations of acute hepatitis. None of the vaccinated children developed symptoms or signs of hepatitis (P = 0.0125), and the estimate of vaccine efficacy was 100%. Two nonstudy children from the center also had clinical and serological evidence of acute hepatitis A. It is concluded that vaccination represents an important method for prevention of hepatitis A transmission in day care centers. The results of this pilot study justify further testing in larger groups.

Vacinacao com BCG por meio de uma tecnica de aplicacao percutanea: observacoes efetuadas em Sao Paulo. / BCG vaccination by a percutaneous administration technic observations made in Sao Paulo

Por meio de dispositivo apropriado e utilizando a amostra Toquio do BCG, foram vacinados pela via percutanea, em Sao Paulo(Brasil) 707 individuos com idades de ate 14 anos. Nao ocorreram disturbios colaterais dignos de mencao e a praticidade do processo de aplicacao ficou evidente. Teste tuberculinico (PPD, Rt-23 2 UT), efetuando 90 dias apos a administracao do imunizante, revelou as seguintes porcentagens,respectivamente, de nao-reatores reatores fracos e reatores fortes: 25,88% 38,76% e 35,36%. O estudo em questao teve,basicamente o intuito de analisar a tolerancia por parte dos membros de casuistica e o comportamento da prova tuberculinica, em observacoes iniciais realizadas no Brasil, concernentes ao metodo encarado como singelo e possuidor de outras vantagens