[Data obtained in more than 20 years of extensive use of Salvioli's diffusing anti-tuberculosis killed vaccine in Bologna].

V.D.S. (Killed T.B. vaccine, Salvioli disperdent) has been administered intradermally to the newborn in Bologna for over 20 yr. It causes a distinct reaction, lasting several weeks, in the injection site and its associated tissues. The alllergy thus constituted is evidence of a highly effective, timely and lasting defence reaction, accompanied by a marked increase in paraspecific reactivity directed to various other sources of infection. These features have been observed and recorded over the long period in which V.D.S. has been widely employed in voluntary vaccination of the newborn in Bologna.