Tuberculosis in Australia: bacteriologically confirmed cases and drug resistance, 2007. A report of the Australian...

The Australian Mycobacterium Reference Laboratory Network collects and analyses laboratory data on new cases of disease caused by the Mycobacterium tuberculosis complex. In 2007, a total of 872 cases were identified by bacteriology; an annual reporting rate of 4.1 cases per 100,000 population. Isolates were identified as M. tuberculosis (n=867), M. africanum (n=4) and M. bovis (n=1). Fifteen children aged under 10 years had bacteriologically-confirmed tuberculosis. Results of in vitro drug susceptibility testing were available for 871 of 872 isolates for isoniazid (H), rifampicin (R), ethambutol (E), and pyrazinamide (Z). A total of 98 (11.3%) isolates of M. tuberculosis were resistant to at least one of these anti-tuberculosis agents. Resistance to at least H and R (defined as multi-drug resistance, MDR) was detected in 24 (2.8%) isolates, all from overseas-born patients; 17 were from the respiratory tract (sputum n=16, endotracheal aspirate n=1). Thirteen patients with MDR-TB were from the Papua New Guinea-Torres Strait Islands zone. Of the 98 M. tuberculosis isolates resistant to at least one of the standard drugs, 54 (55.1%) were from new cases, 9 (9.2%) from previously treated cases, and no information was available on the remaining 35 cases. Seven were Australian-born, 90 were overseas- born, and the country of birth of 1 was unknown. Of the 90 overseas-born persons with drug resistant disease, 66 (73.3%) were from 5 countries: India (n=16); Papua New Guinea (n=15); the Philippines (n=12); Vietnam (n=12); and China (n=11). No XDR-TB was detected in 2007.