The fear or the deadly flu seems to be subsiding, but the Centers for Disease Control (CDC) is concerned about the H1N1 virus appearing again in the fall.

The public could become more vulnerable to the pandemic if the need for protection against it is not recognized, health experts said. The virus has already killed two people in the US and 642 others sick, and might mutate by the start of the traditional flu season.

All in all, there are 1,516 confirmed cases of the virus in 22 countries, according to the U.N. World Health Organization. "The risk of complacency, or a sense that we have weathered this, is a serious one," said Stephen Redd, director of Influenza Coordination at the U.S. Centers for Disease Control and Prevention in Atlanta.

"What we are going to be looking very hard at over the months to come is what's happening in other parts of the world and really trying to understand whether we would be at risk for a resurgence in the fall," Redd said.

CDC officials will try to set up public warnings without making it too alarming, which could risk their authority as the epidemic persists.

US public at risk from complacency over flu -CDC [AlertNet]