Several articles have identified "the mosquito" as the deadliest animal in Africa. This contains a similar bit of indirection. Mosquitoes are rarely a primary cause of death, although there are recorded instances of cattle dying of not enough blood after being caught in East Texas "mosquito storms".sorry I didn't realize you meant Africa only. I read not long ago that it was over 25,000 globally most in India.
Usually it's the pathogens (malaria, dengue etc.) borne by the little flying needlefaces that are the cause of mosquito-borne death. Half a million per year in Africa alone.