Comparative trials of british BCG vaccine double strength, and Danish BCG vaccine, with standard strength British BCG vaccin

Abstract

A trial of U.K. (standard strength) BCG vaccine made from Danish strain 1331 compared with standard strength British vaccine strain 1077 showed that the reactions produced by vaccine made from strain 1331 were too severe for it to be acceptable for routine vaccination of children in the United Kingdom. Two trials of UNICEF (double strength) British vaccine strain 1077 compared with standard strength British vaccine strain 1077 showed that although the double strength vaccine produced slightly larger reactions than the single strength vaccine, the difference was not clinically important. Double-strength vaccine strain 1077 was considered acceptable for routine use in the United Kingdom.