I looked at the start lists. The men are pretty much sealed with Tunisia, Algeria, Libya, Cameroon and Morocco qualifying. They would require three DNFs to miss out since Ghana is way too far. So unless Congo DR is a secret powerhouse or Nigeria decides to show up (where are they?) those will be the five nations.
On the women's side things are a bit more competitive. Nigeria and Tunisia should be safe with Algeria, Cameroon, Madagascar, Morocco and Kenya fighting for two spots. Kenya is a bit of a long shot though. If Madagascar qualify it will be their first athlete in 2016. Also too bad Mauritius only sent three athletes if they had a fourth (even finishing last) they would have had a great shot at winning the quota.