Africa is a very heterogenic country. Many airlines are too small to generate relevant statistical information about its safety; an airline with 4 aircraft would have a record as nice as Southwest's or Qantas' if none of these crashed, but a very bad one if one did.
But in general, Africa has had more than its fair share of crashes. While there are quite few passenger-jets around, there have still crashed an amount comparible to lets say Europe with 10 times as much jets flying. Some airlines, like Tunis Air, RAM or South African have proven to be OK; big airlines with few accidents.
The last passenger casualties with Air Afrique were in 1963, with an old DC-6. With a fleet of 15 aircraft, that's a nice score. (Beware of the domestic Air Ivoire, though).
Air Gabon is a tiny airline with about 7 aircraft. They had a non-fatal ATR incident in 1994 (which ran in a ditch) and a fatal DC-6 freighter crashed in 1979. Not very alarming compared to other airlines, but I would feel a bit less secure with a small airline with such a mixed fleet (these 7 aircraft contain a 747, a 767, 2 727s, 1 737 and 2 Fellowships), which has probably no good maintenance.
nobody has ever died from hard work, but why take the risk?