Two epidemics of tuberculosis in children under three years of age vaccinated with oral BCG in a day-nursery in S. Paulo county, Brazil

Abstract

Two epidemics of tuberculosis in children under three years of age vaccinated with oral BCG, in the year of 1967 and 1969, in a day-nursery in S. Paulo borough, are here described. In 1967 there were 96 children in the place, at first non-reactors, to the standard tuberculine test (PPD, RT-23, 2UT). There were found 19 reactors, being 12 strong reactors (63,2%) and 7 weak reactors (36,8%), and in 15 children or 78,9% of the reactors, the chest X-Rays showed pulmonary abnormalitity. In 1969 there were 62 more children in the institution, initially non-reactors, who were followed-up separately in relation to the 1967 group, although they were in the same environment. There were found 36 reactors to tuberculine, being 29 strong reactors (80,5%) and 7 weak reactors (19,5%) and the chest X-Rays showed pulmonary abnormality in 11 children or 30,5% of the reactors. In that same year there was a tuberculine change in 7 more children, beloging to the non-reactor group of 1967, being 5 strong reactors and 2 weak ones. In both epidemics the tuberculinic changes and the alterations in the pulmonary X-Rays were manifested only in children under 3 years of age, the majority previously inoculated with 3 dosages of oral BCG, with one week interval between two dosages. The source of the infection was a workman who worked in the place among the children under 3 years of age, during approximately two months in 1967 and one month in 1969. The vaccine given by such a method seemed not to have influenced the tuberculine conversions and the development of the specific immunity.