LETTERS TO THE EDITOR BCG vaccination by multipuncture method

I write in response to the article by Al Jarad et al on this topic. The first study to compare the eYcacy of BCG vaccination and its side eVects using the Bignal multipuncture device with the reusable handle and disposable heads was the pilot study of neonatal BCG vaccination carried out in 1992 for the Department of Health in our health authority. In previous studies in neonates and children under two, referenced in the paper by Al Jarad et al, an 18–20 needle percutaneous head gave approximately the same degree of tuberculin conversion as did intradermal vaccination but, to achieve this in older children and adults, 36–40 punctures were required. This would require either a 40 needle head or a double vaccination with two × 18–20 needles. This is why percutaneous BCG is currently only licensed for children aged under two years. Although in neonates and in Al Jarad’s study in older children the rate of tuberculin conversion was lower with percutaneous than with intradermal vaccination, tuberculin conversion does not necessarily equate to lower eYcacy. In the early studies on intradermal BCG the protective eYcacy of the vaccination was related to the presence of a scar after vaccination, but not to the tuberculin test result after vaccination. Those with a BCG scar but a negative post vaccination tuberculin test—that is, no tuberculin conversion—had the same degree of protection against tuberculosis over the 15 years following vaccination as did those with a scar and a positive post vaccination tuberculin test. The multipuncture method is undoubtedly easier to use in neonates because their very thin skin makes intradermal vaccination diYcult, and also in nervous teenagers. Further long term studies on large numbers of subjects would be required to determine whether the technique using only 18 needles in older children is as eVective as intradermal vaccination. Such studies may well prove to be unnecessary. The PHLS system for enhanced tuberculosis surveillance begun this year should, with suYcient cooperation, be able to give the relevant information by the end of 2001 to show whether England and Wales meet the internationally recommended criteria for discontinuation of unselective BCG vaccination in low prevalence countries. BCG vaccination of selective at risk groups, however, would still be required.