Cold, Flu, & Cough Health Center

Killing Flu Germs: What Works?

We’ve all seen news reports about the revolting germs that lurk on the surfaces of things we touch every day.   So as flu season approaches, you might be preparing for battle, a battle against flu germs, a battle waged on doorknobs, and keyboards, and telephones, and other surfaces in your home and office.

But before you douse all your possessions with bleach, there’s one thing you should know: Experts say that you really don’t need to bother. 

“Honestly, if you’re trying to prevent the flu, there’s just not evidence that spraying everything with disinfectant is going to make any difference,” says Christine Hay, MD, assistant professor at the University of Rochester Medical Center.

 Why is that? “Outside of the body, the flu is a really wimpy virus,” Hays says. 

Other flu experts agree.  “There may be some transmission of flu through things like tabletops and doorknobs, but it plays a very minimal role,” says William Schaffner, MD, chairman of the department of preventive medicine at Vanderbilt University’s School of Medicine in Nashville. 

Even so, there are still things you can do to protect yourself from influenza -- and kill some flu germs in the process.  Here’s what you need to know.

How Are Flu Germs Transmitted?

While the flu virus may be a tough guy when it’s inside your body, in the outside world, it’s a frail weakling.  The way the flu is structured, it simply isn’t very resilient.

The flu is nothing like some of the nasty gastrointestinal viruses, like the bane of all cruise ship vacationers, norovirus.  “Some of those viruses can survive on an object for months and withstand cleaning with bleach,” Hay tells WebMD.  “Influenza isn’t like that.”

There have been studies of how long significant amounts of flu germs can survive on surfaces.  Estimates range from a few minutes up to 24 hours, depending on the type of surface.  (It lives longest on hard surfaces.)

While 24 hours seems like a long time, experts downplay the significance.  “I’ve looked at the data, and there just isn’t good evidence that environmental surfaces have a significant role in the transmission of the virus,” says Trish M. Perl, MD, assistant professor of medicine at Johns Hopkins Medical School in Baltimore.  Instead, the flu seems to depend more on direct transmission from an infected person.

Flu Prevention Tip: Clean Your Hands

If you’ve got the urge to clean away flu germs, the best place to start is with your hands.

“Covering your mouth and washing your hands are the two most important ways to stop the spread of the flu,” Perl tells WebMD.

What should you wash with? You might assume that antibacterial soap would be preferable, but that’s the not the case.  First of all, flu is caused by a virus, not bacteria.  Second, any type of soap will do.