From these photos I took off of the internet, the suggestion is that the virus was in Bats, frogs or snakes eaten by people in China. Then the Virus mutated to spread similar to many of the Flu viruses which propagate through saliva and our breadth. We breath out the virus and spread it before it becomes symptomatic and that is what is dangerous about this particular virus (we don’t know who has it for a few days until symptoms appear). Some people will almost certainly be carriers of the virus, never developing symptoms which is not atypical for this type of virus. UPDATE as of 21/29/2020 Recent reports indicate that the incubation period is 3 days from exposure to symptoms.