Have worked in Africa. Most of the comments correct but to say too generally Africa is precisely "this or that" is not correct.
Africa is not a country, it is many individual countries, even more than the US has states(53 in fact) with a population of a billion people total and probably the most diverse place on the planet.
Overall its rougher and poorer than our countries for sure, but there are great variances between regions.
There is South Africa, a country with what we consider very high crime yet with modern infrastructure and well structured paramedic services.
There are of course countries at war, countries pretending not to be at war, though fighting rebels all the time, and also some really peaceful places over there as well, where you will never hear a shot fired.
There is everything from free volunteer work with the aid agencies, minding orphanages(with nothign more than BLS), to high pay medic role contracts, to very high pay hostile/tactical medic roles, to regular 'jobs ' as clinical assistants, hospital workers, up to and including real ambulance jobs as mentioned.
Remember a lot of the big countries like Kenya and Nigeria will have rich districts- almost cities within cities, usually surrounded by the poor. In these districts the residents demand good(for africa) services.
Also keep in mind in the contract side of things a lot of arguments relating to exact qualifications and job titles go out the window. If you are the guy or girl on the ground, and you prove you can do something, you can end up doing anything.
I know ex-army medics who got gigs as paramedics for the UN(which they were a bit worried about as they were not that highly qualified) expecting to be dealing with war like trauma. However it was a peaceful jungle job watching contractors build bridges and one of the boys ended up spending more time helping with the bridge(as he was a builder at one time). Another guy got into logistics arranging cheap rice etc from a local plantations and became a sort of camp cook for everyone as well, and worked his way into being a project manager for the company the UN was subcontracting. This is normal stuff in the contracting world btw.
Its way too much to put it all down here, but for sure if you get a foot in you can do like the rest of professional contractors and stay abroad for ever leapfrogging contract to contract.
I think your best bet is to actually read up a lot on Africa, learn the countries and regions. Join a south african medic forum for example where they use English. And start surfing the job sites like seek.com. Also try the big AID groups webpages, MSF etc, even the free volunteer ones as its a foot in the door.
Also google South African private ambulance services such as
http://www.netcare911.co.za/ and enquire about working there, or taking one of their training courses if you have the money to go.