Yvonne Chaka Chaka on the fight against fake drugs

A campaign to combat counterfeit medicines in Africa has gained the support of two of the continent's biggest musical stars, Yvonne Chaka Chaka and Youssou N'Dour.

Estimates suggest that as mauch as 30% of medicine on sale in Africa is fake, and many of the imposter drugs can have harmful effects or even be deadly.

Yvonne Chaka Chaka spoke to the BBC about the song, Proud To Be, and why she wanted to get involved.