Most treatment for tuberculosis (TB) was developed years ago and is guided by classic public health principles of doing the best for the most people. In contrast, HIV treatment is activist-led and concentrates on empowering individuals and applying the latest research on the ground.
These radically different cultures have been in a decades-long power struggle that reaches all the way up to the World Health Organization's own TB and HIV programmes.
TB and HIV need to be treated together. Potential drug interactions make the timing of treatment crucial, and TB develops differently in someone with HIV.
Despite the difficult history, there are signs that relations between the global programmes to fight TB and HIV are changing, reports Apoorva Mandavilli.
In Rwanda and Kenya, 75 per cent of TB patients are being tested for HIV, an increase from almost nothing 18 months ago.
The World Health Organization now recommends HIV testing for all TB infected people, administering TB drugs for HIV positive people and integrating treatment programmes.