True, but that seem to be a reasonable assumption according to at least some virologists looking at it. There are so many unknowns right now that any modeling

True, but that seem to be a reasonable assumption according to at least some virologists looking at it. There are so many unknowns right now that any modeling is going to have issues, best you can do is state your assumptions clearly, and explore the ones that seem most likely in some depth. Otherwise you just end up with an ensemble of models that could result if nearly anything.