Abstract

PIP: BCG vaccination has been applied on an increasing scale during the last few decades. This vaccination is now being applied to the newborn despite the fact that there is little direct evidence concerning the degree of protection afforded to very young infants. This discussion reviews the evidence that is available regarding vaccination of the newborn from 3 controlled trials that were carried out in the 1930s and the only recent evidence that is available on this question which comes from retrospective studies. The 1st effort to examine the efficacy of BCG vaccination of young infants in a controlled trial was begun in New York City in 1926. Up to 1933, half of the infants (under 1 year old, many under 4 weeks) referred from tuberculosis homes were vaccinated, the others serving as control. There were 3 deaths from tuberculosis among 445 vaccinated children but 18 deaths among 545 controls. During the 14 years of the controlled trial in Saskatchewan Indian infants (begun in 1933), there were 53 deaths among those vaccinated with BCG and 63 among the controls. Among the 306 vaccinated children there were 6 cases of tuberculosis, 2 of whom died. Among the 303 controls, there were 29 cases, 9 of whom died. A study of BCG vaccination of the newborn by a percutaneous multiple puncture method was started by Rosenthal et al. in 1937. It comprised 3381 infants of whom about half were vaccinated during the 1st week after birth if the household members were free of tuberculosis. As regards tuberculosis, the difference in morbidity was highly significant. There were 17 cases among the 1716 vaccinated and 65 cases among the 1665 controls. An interesting analysis of morbidity statistics for different countries was made by Bjartveit and Waaler, who studied the association between the decline of tuberculosis in various age groups and the age at which vaccination was given. This association was pronounced and thus provided evidence of the efficacy of BCG vaccination. Results have been recently published of a retrospective study that concerned 6364 infants who were vaccinated at birth, in Hamburg in 1954, and 9524 who were not. Up to 1971, 9 of the vaccinated and 130 of the unvaccinated children had developed tuberculosis. Of the 30,370 children born in 1963, 27,371 were vaccinated and 2999 were not. There were 11 cases of tuberculosis among the vaccinated and 16 cases among the unvaccinated children over the 8 year follow-up period. At face value, the evidence suggests that BCG vaccination of the newborn confers considerable protection against tuberculosis in infants and young children, yet it must be remembered that the evidence is both scanty and superficial.