I went to west africa vegan and to be frank, it was sometimes challenging. I would bring my own food, nuts, and protein bars, and probably just be prepared to be a bit hungry, or fill up on fruit (which only fills me up for like, 30 minutes).
the worst part is not really being able to ask if it's made with meat broth/lard at some places. but you'll be fine. it might not be as easy as eating in san francisco, but I don't think you'll starve. I haven't yet, in all the places I traveled vegan - ghana, cameroon, ivory coast, brazil, europe, and the 'stans - but to be honest sometimes "lunch" was potato chips. and I don't even like potato chips.