a) it's not a flu (influenza) virus, it's a Coronavirus. If you need a shortform 'rona seems to be quite popular.Last spring we had the capital almost totally isolated from the rest of the country for about a month, just necessary traffic allowed, police on almost all roads blocking. In a few days some invented it as a game to try to look for unblocked roads to go through, in the end it was not very difficult as there just were not enough policemen. No body knows if it worked or not.
But considering this Wuhanflu travelling is not the main problem as that infects nobody. Again preventing large meetings is kind of secondary tactic again. The problem is direct close contact with unknown people, as far as I have seen no government has tried to tackle that directly. all just with indirect measures. Maybe it would be time to try that too, so far most other interventions have not worked that well.
b) the problem is close contact with people you know. it's a lot harder to think of friends as potential carriers and you are likely to spend more time with and be closer to friends than strangers. social gatherings, especially indoors and while eating and drinking, are spreading disasters in the making.