Dr. Kevin Kelleher:

I would think it is much less than 24 hours and may be 12. I honestly do not think it is much longer than that. However, there is clearly an issue around individuals hiding. Unfortunately, we know that a significant number of people do not report that they have symptoms and carry on with life.

That is a separate matter. On the whole, the period for the majority is 12 hours, no more than 24.