The Australian Mycobacterium Reference Laboratory Network reported 1,051 bacteriologically confirmed cases of TB in 2010 (Lumb et al. 2013). Results of susceptibility testing to first-line treatments were available for 1,050 cases (99.9%) and multidrug resistance was reported in 37 cases (3.5%). However, 16 patients with MDR-TB were Papua New Guinea nationals who accessed health services in the Torres Strait Protection Zone. The remaining 21 MDR-TB patients were people who lived in Australia. This represents 2.0% of the bacteriologically confirmed cases of TB. This estimate will be used as the base-case estimate for the prevalence of MDR-TB in TB cases in the economic analysis. An upper limit of 3.5% will be tested in sensitivity analyses, to reflect the proportion of MDR-TB in all bacteriologically confirmed cases of TB in 2010; a lower limit of 0.5% will be used, which reflects the lowest proportion observed by the Australian Mycobacterium Reference Laboratory Network since 1995 (Figure ). This is consistent with proportions observed in Victoria during 2002–07 (0.6%–2.2%) (Lavender, Brown & Johnson 2009).
Figure Percentage of TB cases that exhibited multidrug resistance in Australia, 1995–2010
MDR-TB = multidrug-resistant tuberculosis; TSPZ = Torres Strait Protection Zone