South Sudan: Why was a powerful vice-president fired?

South Sudan's President Salva Kiir has sacked his Second Vice-President Dr Benjamin Bol Mel, who was seen as a possible successor. So with First Vice-President Riek Machar under house arrest charged with treason, how will this latest move by the president affect political stability in the country?Africa finally has its own drug-regulation body following the launch of the African Medicines Agency (AMA). Will it help to transform healthcare systems on the continent?And how much is it costing Angola to have Argentine international football star, Lionel Messi, take part in a friendly match celebrating  the country's 50 years of independence?Presenter: Nyasha Michelle Producers: Yvette Twagiramariya, Stefania Okereke, Piers Edwards and Elphas Lagat Technical Producer: Francesca Dunne Technical Producer: Patricia Whitehorne Editors: Andre Lombard and Alice Muthengi