Dr. Siobhán Kennelly:

It will depend very much on whether somebody had symptoms. I am not a virologist or an infectious disease expert and some of these questions might be better directed to such an expert but essentially patients knowing when they may or may not have had symptoms will influence when we might know when the 14-day period started. In general, it is taken from the date of the first test result that is positive. In the absence of symptoms, the 14-day period is completed from then on.