1 New York University, College of Medicine, 550 First Avenue, New York 16, N.Y.
WHILE DEATHS from tuberculosis have decreased sharply in this country, the number of new cases has not, so that there is still leeway for improvement in the control of this disease. Safe, effective immunizing agents have contributed immeasurably toward the control of other communicable diseases. What is the situation in 1959 with respect to vaccination against tuberculosis? This Commentary and the paper by Barclay in this issue of Pediatrics consider this question.
Already in Koch's day the search was on for a vaccine against tuberculosis. Tuberculin, as well as tubercle bacilli killed or attenuated in various ways and strains of tubercle bacilli derived from cold-blooded animals, proved disappointing. Calmette and Guérin, working with a virulent bovine strain of tubercle bacillus isolated in 1902, found that it lost virulence when sub-cultured at frequent intervals on special media. By 1922, the "BCG" strain appeared stable and was administered orally to infants. Soon afterwards, despite pleas from prominent French clinicians of the day, mass vaccination was undertaken without adequate controls, and the vaccine fell into disrepute.