yes, it is... There's no evidence of cases months earlier. Virus don't typically jump species and are effective immediately. They need time to adapt. Therefore:

yes, it is... There's no evidence of cases months earlier. Virus don't typically jump species and are effective immediately. They need time to adapt. Therefore: a) The virus learned about humans over weeks or months in public with no one noticing b) The virus learned about humans in a lab then leaked resulting in a fast moving pandemic