The virus can take up to 21 days to become symptomatic. More worrisome is that it's been found in fluids up to 60 days post infection. If the flu can spread widely, so can this -- the main limits thus far have been that it doesn't spread via the air, and that it's been geographically isolated. You can't call this outbreak geographically isolated anymore.

http://www.who.int/mediacentre/factsheets/fs103/en/