Effectiveness of BCG Vaccination Against Mycobacterium tuberculosis Infection in Adults: A Cross-sectional Analysis of a UK-Based Cohort. (29th August 2019)

• Record Type: Journal Article
• Authors: Katelaris, Anthea L; Jackson, Charlotte; Southern, Jo; Gupta, Rishi K; Drobniewski, Francis; Lalvani, Ajit; Lipman, Marc; Mangtani, Punam; Abubakar, Ibrahim
• Is Part Of: Journal of infectious diseases. Volume 221:Number 1(2020)
• Page Start: 146
• Page End: 155
• Publication Date: 2019-08-29
• Subjects: BCG -- Bacillus Calmette-Guérin vaccine -- tuberculosis -- vaccine effectiveness; Communicable diseases -- Periodicals; Diseases -- Causes and theories of causation -- Periodicals; Medicine -- Periodicals; Communicable Diseases -- Periodicals; Electronic journals; 616.9
• DOI: 10.1093/infdis/jiz430
• Languages: English
• ISSNs: 0022-1899

Abstract

Abstract: Background: BCG appears to reduce acquisition of Mycobacterium tuberculosis infection in children, measured using interferon-gamma release assays (IGRAs). We explored whether BCG vaccination continues to be associated with decreased prevalence of M. tuberculosis infection in adults. Methods: We conducted a cross-sectional analysis of data from adult contacts of tuberculosis cases participating in a UK cohort study. Vaccine effectiveness (VE) of BCG, ascertained based on presence of a scar or vaccination history, against latent tuberculosis infection (LTBI), measured via IGRA, was assessed using multivariable logistic regression. The effects of age at BCG and time since vaccination were also explored. Results: Of 3453 recent tuberculosis contacts, 27.5% had LTBI. There was strong evidence of an association between BCG and LTBI (adjusted odds ratio = 0.70; 95% confidence interval, .56–.87; P = .0017) yielding a VE of 30%. VE declined with time since vaccination but there was evidence that LTBI prevalence was lower amongst vaccinated individuals even >20 years after vaccination, compared with nonvaccinated participants. Conclusions: BCG is associated with lower prevalence of LTBI in adult contacts of tuberculosis. These results contribute to growing evidence that suggests BCG may protect against M. tuberculosis infection as well as disease. This has implications for immunization programs, vaccine development, and tuberculosis control efforts worldwide. Clinical trials registration: NCT01162265. Abstract : This analysis found BCG was associated with a lower prevalence of LTBI (measured via IGRA) in adults with recent exposure to active tuberculosis. These results suggest BCG may provide durable protection against Mycobacterium tuberculosis infection as well as disease.