Can you enumerate the dangers that the two friends will face in Africa - sudden malnutrition? If you are referring to armed conflict or the danger of being abducted by the local African warlord[1], then you might be happy to know that such dangers are highly localized and the high-risk areas easily avoided; after all, Africa is a large place (larger than the US, China and most of Europe. Combined[2].

1. Common trope

2. http://io9.gizmodo.com/africas-true-size-will-blow-you-away-...