Dallas ? As we enter peak flu season, Dr. Donna Casey hopes her friends and family are using this year’s Christmas gift from her: a toothbrush sanitizer.

“If you cultured a toothbrush, you’d be appalled by all the germs there,” said the internist affiliated with Presbyterian Hospital of Dallas. “Same goes with a grocery cart or elevator button or any handrail in an airport.”

Say you brush against the offending item and then touch your mouth. Quicker than you can say gesundheit, you’ve become a statistic: You’re among the 5 percent to 20 percent of Americans who, according to the Centers for Disease Control and Prevention, will catch the flu this year.

A serious illness characterized by fevers, aches and chills, the flu also has become big business. Kleenex Anti-Viral Tissues, which claim to kill 99.9 percent of cold and flu viruses, are hot sellers. Alcohol-based hand sanitizers have become ubiquitous. And, like the toothbrush sanitizer, a whole generation of gadgets relies on ultraviolet rays to zap bugs and purify everything from countertops to rooms.

“I don’t want to turn people into germaphobes, but a lot of this stuff really does work,” Casey said.

Consider that the influenza virus has been known to thrive for up to eight hours on certain surfaces or in the air. Humidifiers with ultraviolet technology will pull oxygen from the room into a chamber that destroys germs. Or consider a handheld wand such as the $60 Cleanse Light, available at Brookstone, which shoots out UV rays. Swipe the unit over anything, and you’ve become a germicidal terminator.

The best protection

Innovative and effective as they may be, no one is claiming that products can take the place of the most-recommended defense against the flu: a vaccination.

Beyond the high-tech gear and the vaccination, most doctors recommend going old school to safeguard yourself. That means a healthy diet, exercise and vigilant hygiene. Frequent and thorough hand washing remains the first line of defense.

“A lot of people ask, ‘What’s the best soap to use, antibacterial or regular soap?’ ” said Dr. Jane Sadler, a family physician on staff at Baylor Medical Center at Garland, Texas. “In order for antibacterial soaps to truly be more effective than regular soaps, you need to do about a 30-second scrub, and most people don’t do that.”

Sadler likes antibacterial hand-sanitizing gels, too.

“It’s recommended that you use about a quarter-sized dollop of hand gel,” she said. “If your hands are dry in 10 to 15 seconds, you probably didn’t use enough.”

Despite the high-tech trend toward flu-busting, basics such as avoiding sick people, plus good hygiene, can make a huge difference in whether you get sick.

But what if, despite all your best efforts, you get the flu?

“I tell my patients to call me within 48 hours : and I’ll give them Tamiflu, which is the No. 1 way to knock the flu out. If you don’t take Tamiflu, you can expect the flu to take 10 to 14 days to run its course,” Casey said.