I think the point—and this is sort of a gradient—was literally December 31. First seeing that information certainly caused some alarm. Around the middle of January—and I'd have to double-check the exact date—was when the first case showed up in Bangkok.
I'll give you a bit of a sense of the increasing concern.
When we learned that this was a novel coronavirus, I believe somewhere around January 8 or so, there was concern for all the reasons I mentioned earlier, MERS and SARS, and comparing those: no vaccine, no effective antivirals, no underlying immunity and we were in the middle of flu season.
What we had been learning up until that point is that the number of cases being reported in China were in the dozens. When the case showed up in Bangkok, which was the top place we had concerns about because of the movement of travellers from Wuhan out into the region, in a city of 11 million.... The math doesn't work if you have a case show up in another city and knowing the volume of travellers who were leaving. That was the moment for me and our team, when we were really quite concerned.
Again, we didn't have all the answers, but we were quite concerned that this was a novel coronavirus. The outbreak was much larger than it appeared to be. This inevitably told us this was not just a spillover event. This was not just the people who were at the market who became infected. If there were hundreds or thousands of cases, this had to be something that was more efficiently being spread from person to person.
It was roughly around the middle of January that we had serious concerns about how this might unfold.