Impact of Targeted Tuberculosis Vaccination Among a Mining Population in South Africa: A Model-Based Study

Am J Epidemiol. 2017 Dec 15;186(12):1362-1369. doi: 10.1093/aje/kwx192.

Abstract

Optimizing the use of new tools, such as vaccines, may play a crucial role in reaching global targets for tuberculosis (TB) control. Some of the most promising candidate vaccines target adults, although high-coverage mass vaccinations may be logistically more challenging among this population than among children. Vaccine-delivery strategies that target high-risk groups or settings might yield proportionally greater impact than do those that target the general population. We developed an individual-based TB transmission model representing a hypothetical population consisting of people who worked in South African gold mines or lived in associated labor-sending communities. We simulated the implementation of a postinfection adult vaccine with 60% efficacy and a mean effect duration of 10 years. We then compared the impact of a mine-targeted vaccination strategy, in which miners were vaccinated while in the mines, with that of a community-targeted strategy, in which random individuals within the labor-sending communities were vaccinated. Mine-targeted vaccination averted an estimated 0.37 TB cases per vaccine dose compared with 0.25 for community-targeted vaccination, for a relative efficacy of 1.46 (95% range, 1.13-1.91). The added benefit of mine-targeted vaccination primarily reflected the disproportionate demographic burden of TB among the population of adult males as a whole. As novel vaccines for TB are developed, venue-based vaccine delivery that targets high-risk demographic groups may improve both vaccine feasibility and the impact on transmission.

Keywords: South African gold mines; TB vaccine; mathematical modeling; targeted vaccination; tuberculosis.

MeSH terms

  • Anti-Retroviral Agents / therapeutic use
  • BCG Vaccine / administration & dosage*
  • Coinfection
  • Computer Simulation
  • HIV Infections / drug therapy
  • HIV Infections / epidemiology
  • Humans
  • Immunization Programs / statistics & numerical data*
  • Male
  • Mining*
  • Models, Theoretical*
  • Socioeconomic Factors
  • South Africa / epidemiology
  • Tuberculosis / epidemiology
  • Tuberculosis / prevention & control*
  • Tuberculosis / transmission

Substances

  • Anti-Retroviral Agents
  • BCG Vaccine