While there are a succession of drugs which offer some control over the disease in many cases, a small number of patients do not respond to these.

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The city's affluence has spawned turf wars between rival gangs, especially over control of the booming market in amphetamines and other drugs.

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But analysts are divided over whether the Tuareg revolts have been driven by genuine political grievances or efforts to defend control of drugs, arms and migrant-smuggling routes.

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