M&A WATCH- South African investment firm Tana Africa Capital has doubled its stake in Alexandria Medical Investments Company to 49% from 25%, the local press reports, citing sources familiar with the transaction. Tana acquired its stake in the company earlier this year for an undisclosed price in a transaction that included minority ownership of Mabaret El Asfara Hospitals Group, which in turn is majority-owned by Alexandria Medical. Tana and Alexandria Medical are looking to set up a joint healthcare investment firm to expand the company’s footprint nationwide.