Directly via bat guano farming and direct human/bat contact (plus some presence of live bats in wet markets and the workers that need to clean those). Indirect

Directly via bat guano farming and direct human/bat contact (plus some presence of live bats in wet markets and the workers that need to clean those). Indirectly via animals like minks/civits being farmed. The bats can occasionally infect those animals, when those zoonotic jumps happen there's then a large bioractor of animals in close contact, resulting in a "serial gain of function" experiment to produce a virus which is adapted to those animals and can spread. Every factory farm is a stochastic virus research laboratory that isn't even BSL-1 trained.