Ziv et al. [14] explored the potential public health impact of preand
post- infection vaccines in high TB incidence countries. They
demonstrated that pre-infection vaccines that reduced susceptibility
to infection would more quickly reduce the number of new
infections than post-infection vaccines, while post-infection vaccines
would be more likely to have a more rapid impact on the
reduction of TB disease. Within 30 years, however, pre-and postexposure
vaccines may be equally effective at reducing TB disease.
For a vaccine to contribute to global control of TB, the authors suggested
that both pre- and post-infection protective functions are
needed.