BCG vaccination and Mycobacterium tuberculosis infection in adults

  • Katelaris AL & al.
  • J Infect Dis
  • 29 Aug 2019

  • curated by Sarfaroj Khan
  • UK Clinical Digest
Access to the full content of this site is available only to registered healthcare professionals. Access to the full content of this site is available only to registered healthcare professionals.

Takeaway

  • Bacillus Calmette-Guérin (BCG) vaccine was associated with a lower prevalence of latent tuberculosis infection (LTBI) in adults with recent exposure to active tuberculosis.

Why this matters

  • Findings contribute to growing evidence that BCG may provide protection against Mycobacterium tuberculosis (Mtb) infection as well as disease.
  • It has implications for immunisation programmes, vaccine development, and tuberculosis control efforts worldwide.

Study design

  • Cross-sectional study of 3453 contacts of patients with LTBI who participated in the UK PREDICT study.
  • Vaccine effectiveness of BCG ascertained against LTBI, measured through interferon-gamma release assays (IGRAs).
  • Funding: None disclosed.

Key results

  • Of 3453 patients, 86.9% (3000/3453) had received BCG vaccination.
  • The overall prevalence of LTBI was 27.5% (951/3453), 27.0% (809/3000) in those vaccinated and 31.4% (142/453) in the unvaccinated.
  • After adjustment for confounders, significant association was observed between BCG and LTBI (OR, 0.70; 95% CI, 0.56-0.87; P=.0017).
  • In those vaccinated at age ≤2 years, protection was greater in those vaccinated 11-20 years ago (OR, 0.55; 95% CI, 0.33-0.90) than those vaccinated >20 years ago (OR, 0.78; 95% CI, 0.60-1.00).

Limitations

  • Observational design cannot prove causality.
  • Risk of confounding.