[sjg007]

You have previous known infections in the villagers who interact with bats and then travel to say the Wuhan live market. We study these viruses because we know they infect humans. The Spanish flu was a bird flu. There were no biosafety level 5 labs back then. We get viruses from other animals all the time.

[throwanem]

Nitpick: there's no such thing as BSL-5. The scale tops out at level 4. Coronaviruses are handled at BSL-3.