BCG Revaccination Trial

PI : Laura Cunha Rodrigues and Mauricio Barreto
Funders: DFID, Brazilian Minister of Health

A cluster-randomized trial involving more than 200 000 school-aged children from Salvador and Manaus (BCG-REVACC) followed for over 20 years. The trial tested BCG-VE of a second BCG dose against tuberculosis and against leprosy when administered at school age. The trial also allowed studying BCG-VE of single dose BCG vaccination when administered to individuals at different age groups who reside in different ecological settings. The study reported on efficacy of revaccination, first vaccination at school and neonatal vaccination, and duration of neonatal protection in two follow up periods, as well as validity of scar reading as a measure of previous BCG vaccination, parallel immunological studies, frequency of adverse events, and contrasted efficacies in Manaus and Salvador to inform the questions of masking or blocking mechanism for BCG.  As ascertainment of cases is through routine tuberculosis and leprosy programmes, the follow up continues.