One hundred years of BCG vaccine

The BCG vaccine was given for the first time in 1921, in Paris, to a newborn of a mother with tuberculosis. Between 1924 and 1960, the Pasteur Institute delivered BCG cultures to more than 50 laboratories around the world. In 1925, Dr Andrés Arena introduced the BCG seed to Argentina, where the vaccine began to be produced and applied orally to newborns. The original strain underwent diverse genetic changes in different parts of the world, which did not seem to affect its protective efficacy. In Argentina, a study (1978-1985) showed that BCG prevents primary TB in general, and has 100% efficacy in meningitis and other extra-pulmonary TB locations. BCG effect is independent of TB control measures (case detection and treatment). Furthermore, BCG provides nonspecific protection from various infections and is used in the treatment of bladder cancer. By 2020, at least five technologies had already been established for the future development of anti-TB vaccines: cellular vaccines, protein subunits, nucleic acids, with adenovirus vector, and with recombinant influenza virus as a vector. There are currently more than 20 TB vaccine candidates under evaluation. History teaches, and the COVID-19 pandemic has confirmed, that vaccination is a fundamental instrument for the control of infectious diseases. Until a more effective vaccine becomes available, BCG will continue to be included in the Argentine National Vaccination Calendar for application to newborns.