By Elizabeth Landau, CNN
(CNN) - It's everywhere you look - in schools, in shopping malls, in day care centers, in offices.
[cnn-photo-caption image= http://i.cdn.turner.com/cnn/2009/HEALTH/11/27/hand.sanitizer.basics/story.hand.sanitizer.gi.jpg caption="When soap and water aren't available, hand sanitizer is a good solution, experts say."]
Hand sanitizer has become ubiquitous after the outbreak of the novel H1N1 flu virus. But what are its special powers? Does it really protect from viruses? And what's the best way to use it?
When it comes to choosing a hand sanitizer, the Centers for Disease Control and Prevention recommends the ones with alcohol for protecting against the H1N1 flu. The optimum proportion is 60 to 95 percent alcohol, according to this CDC chart showing the relative effectiveness of different types of sanitizers.
Dr. Anne Schuchat, director of the National Center for Immunization and Respiratory Diseases, said in a recent briefing that people should wash their hands often with soap and water or alcohol-based hand sanitizers to combat the flu.
"We are beginning to see some declines in influenza activity, but there is still a lot of influenza everywhere," she said.
The CDC said that according to some estimates, up to 80 percent of all infections get spread by hands.