TB is the leading infectious killer of HIV positive people in the developing world, killing up to half of HIV/AIDS patients worldwide. Individuals are living with HIV, but dying from TB.1


Meanwhile, however, the spread of HIV/AIDs and the emergence of multidrug resistance pose major challenges to further progress in combatting the TB epidemic, especially in certain regions.


Persons living with HIV/AIDS are far more vulnerable to TB, due to their severely compromised immune systems. Moreover, TB is particularly difficult to diagnose in this context, and yet early diagnosis is essential. HIV/AIDS mortality can often be attributed to missed or delayed TB diagnosis. In 2009, 1.4 million (12%) of the new TB cases were HIV-positive, as were 400,000 (about 23%) of those dying with TB. Most of those co-infected with TB and HIV reside in sub-Saharan Africa.


Resistance to the drugs typically used for treating TB represents another growing challenge. In 2008, there were nearly half a million new cases of multidrug resistant TB (MDR-TB). This represents about 5% of all new TB cases globally; but MDR-TB accounts for a much higher percentage (as high as 28%) in a few regions, notably some parts of the former Soviet Union. Accordingly, the increasing prevalence of MDR-TB is changing the character of what needs to be determined at point of treatment. Drug susceptibility information is often needed to guide initial treatment decisions.