The bats are believed to contaminate fruit, and the virus is passed on to organisms eating the infected fruit, be they humans, non-human primates, or possibly pigs.
Dogs can catch the virus from eating the carcass of an infected animal, but remain asymptomatic.
The bats and the non-human primates are eaten as "bushmeat" and in the process of butchering or cleaning, an individual can become infected (via any small cut or mucous membrane contact) while butchering the animal or from eating the animal if undercooked.
Once a human has it, things may or may not escalate from there.
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