Research Partnerships with Developing Countries
A Programme funded by Swiss National Science Foundation (SNSF) and Swiss Agency for Development and Cooperation (SDC)

Tuberculosis epidemiology in Papua New Guinea and drug resistance monitoring using molecular markers

Background: In 2005 more than 1.5 million people died from tuberculosis (TB), and 8-9 million people were newly infected with Mycobacterium tuberculosis. TB is a major cause of death among HIV patients. The long therapy and lack of alternative drugs led to the emergence of resistant TB strains and resistance has become a major threat to TB control programs world wide. It is estimated that about 4% of TB patients carry multi-drug resistant Mycobacteria. the World Health Organization considers Papua New Guinea (PNG) as "high burden" TB country. Estimates on multi-drug resistant TB cases increased from 3.6% in 2004 to 5.3% in 2006. However, there is no systematic monitoring in PNG and due to the worsening situation of the health system, the burden of TB is likely to be underestimated. High rates of treatment failure have been reported and a hospital based study showed 17% of primary resistance and 8% of MDR-TB prevalence in 2006. This and a dramatic increase in HIV infections requires urgently accurate assessment of the TB situation in PNG. Approach: In collaboration with the PNG Institute of Medical Research (PNGIMR) we will establish a TB cohort to estimate the burden of TB, to assess drug resistance, and to identify circulating M. tuberculosis strains. The cohort is established according to the National TB control program using a 'Directly Observed Treatment Short Course' (DOTS). Yet, there is no drug susceptibility monitoring and we will introduce minimal susceptibility testing in collaboration with the Australian reference laboratory. In addition, we will locally establish molecular typing methods to characterize mutations associated with resistance to drugs. We will also validate molecular diagnostic assays for sensitivity, feasibility, and cost for rapid 'on site' detection of TB. Several diagnostic methods (e.g. real-time Polymerase Chain Reaction (PCR), antigen detection in urine, etc.) will be compared to sputum smear microscopy and liquid culture. The origin and the dynamics of TB infections in PNG will be determines by standard spoligotyping techniques, Mycobacterial Interspersed Repetitive Unit-Variable Number Repeat (VNTR-MIRU)-typing, and SNP analysis for the characterization of circulating M. tuberculosis strains. Expected outcomes: We will introduce modern diagnostic, genotyping, and drug susceptibility testing techniques to provide essential information to the National TB Control Program for a better understanding of the epidemiology, dynamic, and evolutionary origins of TB in PNG. Furthermore, we will establish research capacity in this area at the PNGIMR by training lab technicians and post-graduate scientists from PNG.

Contacts:
Herr Hans-Peter Beck
Swiss Tropical and Public Health Institute
Socinstrasse 57
CH-4002 Basel

e-mail: hans-peter.beck(at)unibas.ch

Mr. Peter Max Siba
Papua New Guinea Institute of Medical Resear
P.O. Box 60
PG-EHP Goroka

e-mail: peter.siba(at)pngimr.org.pg