B.c.g. Vaccine and Phlyctenular

THOUGH the aetiology of phlyctenular conjunctivitis is doubtful, evidence has been accumulating that the phlyctenule (a solid pustule) is an allergic anaphylactic phenomenon. The sensitizing agent is a protein and is endogenious and of bacterial origin. Various proteins, such as the gonococcal protein may give rise to phlyctenules, but the tuberculo-protein is the most frequent and obvious (Duke-Elder, 1938). Guillery (1921) found that phlyctenules could be produced by sensitizing non-tuberculous rabbits and then injecting tuberculin. A similar phenomenon has been appearing lately in these Islands following upon mass vaccination in the early months of 1950 of young people between the age of 2 and 18. The B.C.G. vaccine is produced from a bovine type of tubercle bacillus, after it has been cultured for 13 years in a special medium. Though the bacillus loses its power to produce tuberculous disease, it retains the power of the tubercle bacillus to develop a relative immunity against tuberculous disease. Only persons showing no reaction to a tuberculin test, that is non-reactors to tuberculin, were B.C.G. vaccinated. In the Malta campaign the Adrenaline-Pirquet test was used. This consists of standardized tuberculin (1.7 times international standard), to which adrenaline has been added. The non-reactors have either too few antibodies to afford any protection against tubercle bacilli, or no antibodies at all because they have never been infected or because the infection occurred a long time ago. These non-reactors are converted to reactors by means of the B.C.G. vaccine. A reading of the test is made on the 3rd day, when positive reactions show an area of infiltration of at least 4 mm. (Weidemann, 1950). Several methods of administering the vaccine have been employed, and the standard intradermal method has been found to be the best. After an intradermal injection of the B.C.G. vaccine, what one might call a normal " B.C.G.-itis " occurs. There is multiplication of the bacilli at the site of the injection, early propagation of the bacilli to the