[HIV-infection, AIDS and BCG vaccination]

Bacille Calmette-Guérin (BCG) has been widely used as a safe and effective vaccine for the protection of tuberculosis, but recent epidemic of human immunodeficiency virus (HIV) infection evoked serious concerns about the safety of BCG when vaccinated to HIV-infected persons: that is, because BCG is a live, though avirulent, bacterial vaccine, it might grow in immuncompromised host and might cause dissemination and/or exacerbated local adverse reactions. In fact, during the decade since the first report on AIDS in 1981, several reports were published on the adverse reactions, systemic or local, induced by BCG in HIV-infected persons. In this paper, the present author attempted to review such reports as comprehensively as possible. From critical examinations of the literatures, it was concluded that: 1) None of the reports dealing with dissemination of BCG provided satisfactorily enough evidence to identify the isolated mycobacteria as Mycobacterium bovis BCG. In some cases, infection with wild strain of M. bovis, instead of BCG, should be considered as more plausible pathogen. Especially, two reports, which suggested the late reactivation and dissemination of BCG vaccinated 30 years ago, could not be accepted without more detailed description of the procedures and results of the identification tests. In some cases, application of BCG were considered to be inappropriate. According to the present author's judgement, when BCG was applied appropriately as an anti-tuberculosis vaccine, generalized infections were most plausively induced by BCG only in 4 cases during this decade. 2) As for the local adverse reactions, many reported cases of outbreak of local adverse reactions, such as local ulceration and supprative lymphadenitis, were not related to HIV-infection at all, but were due to the usage of an inferior vaccine produced by a specified manufacturer (Pasteur Institute, Paris). Conclusion was that BCG could be safely vaccinated to children born from HIV-seropositive mothers, even if children themselves were also infected with HIV, so long as BCG vaccine of good quality was used. 3) Positive conversion rate of post-vaccination tuberculin skin-test seemed to be lower in HIV-infected children than in children born from HIV-seronegative mothers. But, about 30% of the HIV-infected children converted to tuberculin-positive after BCG vaccination suggesting the effectiveness of the vaccination for the considerable fraction of the babies at the highest risk of tuberculosis infection. Positive conversion rate was much higher in HIV-noninfected children born from HIV-seropositive mothers.(ABSTRACT TRUNCATED AT 250 WORDS)