The prevalence of neutralizing antibodies for the three types of polioviruses and the immunity levels of different age groups were determined through a seroepidemiological survey, in a population of 0 to 12 year old children, living in the city of S. Paulo and attending the Menino Jesus Hospital. The results showed a high number of children susceptible to infection by polioviruses, mainly in the 9-12 month age bracket where the proportion of individuals completeley susceptible was 42.5%. In this group […]

The prevalence of neutralizing antibodies for the three types of polioviruses and the immunity levels of different age groups were determined through a sero-epidemiological survey, in the elementary school children population from the São Paulo public school system. The investigation was based on a representative sample of the school population – a total of 1.486 children was studied – and the immunity levels were determined in 13 Public Administrative Regions, as well as in the three geographical zones of S. […]

In a probabilistic sample of the elementary school children belonging to the S. Paulo public school system, a survey was conducted in order to establish 1) the vaccination status of the children – number of doses of oral polio vaccine, 2) the kind of housing – private home or slum, 3) the cultural status of the mother – literate or illiterate. These factors were studied in relation to the prevalence of neutralizing antibodies and the immune status to poliomyelitis of […]

The situation of poliomyelitis in the city of São Paulo is analysed by means of an epidemiologic surveillance parameter – the “r” factor of immunization events. The results of a recent sero-epidemiologic survey realized in this City were transformed into the catalytic growth curve y = a + (1 – a) (1 – e-rt). The informative value of the survey is therefore considerably enhanced. The analysis showed that about 50% and 60% of the population of children 0-10 years old […]

The efficacy of oral polio vaccine (OPV) was determired in infants immunized according to the currently recommended vaccination scheme in the city of S. Paulo. Trivalent OPV was administered to the infants at 8 week intervals, begining at 2 months of age, in well controled conditions at the Experimental Health Unit of the Escola Paulista de Medicina. The study showed that the administration of 2 doses of OPV resulted in poor seroresponses and was not sufficient for effective immunization of […]

Some characteristics of epidemiological relevance of the behavior of poliomyelitis in some Health Districts of Greater S. Paulo were studied, special emphasis being put on its occurrence in children of less than one year of agre. Next, the results of serological investigation, performed by means of neutralization tests, on pregnant women attended by Health Centers in sixteen Health Districts of Greater S. Paulo were analysed. Based on these observations the authors draw attention to certain conditions poliovirus infection in children. […]

An epidemiological analysis was carried out on 898 children, in order to study the immune response to polioviruses 1, 2 and 3 by means of the measurement of neutralising antibodies. Information was obtained from 522 (58.1%) of the children with regard to their vaccinal position by examination of the observations recorded on the individual vaccination certificates. In this subgroup the immune status in relation to number of Sabin type oral vaccine doses was analysed. The analysis demonstrated a high proportion […]

Various hypotheses have been proposed to explain the diminished efficacy of the oral polio vaccine in underdeveloped tropical regions. In this study, the influence of mild to moderate chronic malnutrition on the development of antibodies to the 3 types of polioviruses was investigated in Brazilian Amazonian children. Vaccines were administered to 106 normal and stunted children, between 5 to 14 months of age, who were not suffering from acute malnutrition (wasting), in poor peri-urban slum areas of Manaus (AM) and […]