In Mexico, the A/H1N1 influenza topped the agenda at a gathering of medical experts and government officials from around the globe. WHO Director-General Margaret Chan hosted the meeting which is aimed at relaying the latest information on the global menace.

During the meeting on Thursday, Margaret Chan urged governments to remain vigilant. She noted the A/H1N1 virus usually causes mild symptoms that go away without medication in most patients.

But she said care-givers should be alert for warning signs of severe cases.

Margaret Chan said, "Ladies and gentleman, between the extremes of panic and complacency lies the middle ground of vigilance. This meeting is all about vigilance, taking stock of what we have learned and preparing for whatever surprises this precious new virus delivers next."

Chan also slammed nations that choose to seal borders and limit travel when faced with the appearance of the virus.