What makes you think that God isn't intervening in Africa?
There are numerous charities (many of them Christian) that are operating in Kenya and other parts of Africa. Many Christians feel called by God to donate their time and/or money to help the children of Africa. Because of those charities, many African children are given food, medical care and an education. Many of those children have gone on to lead happy lives. Just look at the story of John Dau, one of Sudan's lost boys. http://www.nationalgeographic.com/field/explorers/john-bul-dau.html
John is quoted as saying "I feel I survived because God wants to do something with my life. I don't want to waste any of the time I have left. So many people are still in Sudan needing clinics, schools, and churches. I cannot forget them." Obviously, he believes that God intervened on his behalf.
I know people that have been in the mission field in Africa. I have heard from them over and over that going to help in a 3rd world country is one of the most faith-strengthening things you could ever do. They tell me that they have seen prayers answered all the time in Africa. The situation in Africa is far from ideal but it isn't hopeless either. I urge anyone with a heart for Africa to get involved with a charity such as Doctors Without Borders or World Vision. Seeing the hope that those kids have and the smiles on their faces will change your life.