TUBERCULIN SENSITIVITY IN GUINEA-PIGS AFTER VACCINATION WITH VARYING DOSES OF BCG OF 12 DIFFERENT STRAINS

  • 1 January 1976
    • journal article
    • research article
    • Vol. 53  (4) , 435-443
Abstract
Twelve BCG strains were ranked in terms of tuberculin conversion in guinea-pigs according to the minimum [skin] sensitizing dose. For 10 of these strains, this minimum dose is very low, ranging from 5-50 culturable particles. The traditional practice of tuberculin-testing guinea-pigs that were vaccinated with a full human dose of BCG (of the order of 106 culturable particles) has such a low discriminating power that it is useless as a routine test for currently used vaccines. The ranking obtained in this model was largely but not completely in accordance with similar rankings in other models. The Tokyo strain and, to some extent, the London strain ranked comparatively lower than they do in children. The pronounced lack of virulence of the Prague strain was confirmed.