Drug resistance

Drug Resistance: tuberculosis

The challenge

Anti-tuberculosis (TB) drug resistance is a major public health problem that threatens the success of DOTS, the WHO-recommended treatment strategy for detection and cure of TB, as well as global tuberculosis control.

WHO/IUATLD Global Project on Anti-tuberculosis Drug Resistance Surveillance

In 1994, due to lack of standardized data on anti-TB drug resistance and in an effort to estimate the global prevalence of resistance, WHO, International Union Against Tuberculosis and Lung Disease (IUATLD) and other partners developed the Global Project on Anti-tuberculosis Drug Resistance Surveillance (DRS). The project assembled a network of Supranational Laboratories to aid National Reference Laboratories in conducting quality assured drug susceptibility testing in conjunction with national or area anti-TB drug resistance surveillance.

The project is now in the process of expanding implementation of the survey to new countries and repeating previously surveyed countries after five years in order to observe trends.

Basic Principles of the Global Project

  • Accurate representation of the sample studied and careful calculation of its size
  • Data collection and analysis which differentiates between new and previously treated cases
  • Internationally accepted methodology and quality control of drug testing

Objectives of the Global Project

  • Estimate the magnitude of the anti-TB drug resistance levels and pattern
  • Monitor drug resistance trends
  • Evaluate the effectiveness of TB control programmes
  • Plan and evaluate interventions and preventive activities
  • Inform TB treatment policy at country level
  • Strengthen laboratory capacity at country level through yearly proficiency testing and training courses in drug sensitivity testing
  • Advocate to increase political commitment Identify research needs

Activities

  • Anti-TB drug resistance surveys
  • Laboratory capacity strengthening
  • Laboratory training in drug sensitivity testing
  • Updating of guidelines in anti-TB drug resistance surveillance
  • Coordination of international quality assurance activities, including shipment of strains for proficiency testing and quality assurance
  • Coordination of Supranational Laboratory Network
  • Development of SDRTB4 software