MONDAY, May 11 (HealthDay News) -- Dr. Charles Ericsson, head of clinical infectious disease at the University of Texas Medical School in Houston, spoke to HealthDay about what scientists know right now about the swine flu outbreak:

What exactly is the swine flu?

"Swine influenza is a known cause of flu in pigs. But once in a while, through mutations, it can acquire the ability to attack humans," Ericsson explained. Formally named swine influenza A H1N1, this strain "appears to have components from human, pig and bird viruses," he said.

How easy it is to become infected?

That's not yet entirely clear. "We know it's passed on through the 'droplet route,' which means that if I'm within three to six feet of somebody and they cough or sneeze I might get some of that spray inhaled through my eyes or nose," he said. "If that happens, and if they have the flu, you can easily get it." It's less clear if you could be infected simply by being in a room where exhaled droplets might still be lingering. As with other flu viruses, people can sometimes become infected by touching something with a virus on it -- a desktop, a doorknob -- then touching their eyes, nose or mouth, according to experts at the U.S. Centers for Disease Control and Prevention. You cannot get swine flu from eating pork.

What can I do to protect myself?

"Cough etiquette is the critical thing. You should be cautious about your own behavior -- covering your mouth and nose when you cough or sneeze in public," Ericsson said. Avoiding crowds, and avoiding folks who are sick or don't use "cough etiquette" is also important, experts say, as is avoiding handshakes, kissing, or touching your eyes, nose or mouth. Also very effective: frequent hand washing, using either soap and water or alcohol-based hand cleaners. The effectiveness of face masks is still "controversial," Ericsson said. If a true pandemic emerges, then mask wearing "might not be a bad idea" in crowded environments, he said. "And if you are ill you should certainly stay home from work" to avoid spreading the illness, he added.

What are the symptoms of infection?

"Basic flu-like symptoms: a high fever, a bothersome dry cough, maybe a little gastrointestinal upset like belly pains or diarrhea, and general malaise," Ericsson said. "Basically you will feel just plain rotten." Flu symptoms typically appear within hours, experts say, whereas common cold symptoms emerge more gradually, are milder, and only rarely include high fever. "Typically, most people with any significant flu are going to have a fever of at least 101," Ericsson said.