Easy to say with the benefit of hindsight and when much of the population of the world is scared. Much harder to achieve when it's all something in a place thousands of miles away and many people think it's nothing more than a bit of winter flu
Flights were not frozen for SARS in 2003 or pig flu in 2009, yet there was little impact in the UK. How would politicians have convinced the masses that this time it would be different without a sizeable number of deaths in countries nearby ?