There is scant room for celebration on this year’s World Tuberculosis Day, with the disease still imposing a heavy burden on humanity. Fresh efforts could and should be made to improve a response which is worsening the threat from the most severe forms of infection.
Despite modest recent reductions in overall impact, TB still infects 9.4m people and kills 1.7m annually. More worryingly, multi-drug resistant (MDR) TB infects 440,000 and extensively drug resistant (XDR) TB another 27,000. These cases are very difficult to treat.
The greatest barrier to progress is the poor quality of vaccines to prevent, diagnostics to analyse and drugs to treat TB. Fresh funding and new incentives are needed to stimulate new technologies, some of which are already in development but are currently threatened by budget cutbacks.
Current medicines, which must be used over a minimum of six months, are a particular obstacle. They are of variable quality and bring unpleasant side-effects. When not taken as prescribed, they generate resistance, fuelling MDR and XDR TB, which has now been identified in 69 countries.
One problem is that the basic TB drugs are often of poor quality, or not taken consistently in the right combinations. Another is that only half of the world’s estimated MDR cases are even diagnosed and just a 10th of these treated with more potent alternative “salvage” medicines. Giving MDR patients the basic drugs instead triggers further resistance, doing nothing to help them recover and everything to spread their more dangerous forms of infection to others.
Part of the solution is money. Salvage treatments are more expensive, as are new diagnostics which can more rapidly and reliably detect TB and distinguish its MDR form. Yet donors are pulling back, and countries – including the richer emerging countries such as India and China with a high burden – need to do far more to help themselves.
Better use of existing money would also help. Salvage TB drugs are very expensive, with irregular orders in small quantities doing little to encourage drug manufacturers to enter the market or provide regular supplies.
Pooling existing drug purchase funds from different countries, supplemented with extra donations, would provide a larger and more certain market to stimulate more production of higher quality and more affordable drugs reliably.
Tackling TB will be expensive. The price of not doing more will be greater.