Antrax spores on the ground (occurs naturaly) get eaten, and the animals die. Seems this happens all the time there, except 120 seems like alot to me. Then is spreads as people or animals eat the meat of the infected animals. Scary.....

It might be an import from Europe (not a deliberate one.) If you (or an animal) has walked in an area where there is anthrax, you can carry the spores to another area. So it's not impossible that someone was walking on ground infected with these spores and went to Africa... and the spores found a temporary host in the hippos.