As the days shorten toward winter, sniffles and sore throats return. Noses start dripping, and all too soon you’ve got aches and pains, fever and malaise. And so do your kids, or your colleagues, or your friends.

This is the onset of cold and flu season, when germs travel easily from person to person as we spend more time close together indoors. And everything can be a good breeding ground for germs: computer keyboards, the knob on the door into your office, the telephone you use, the subway seat where someone coughs behind you, the escalator railing, the shopping cart handle.

Germs get spread by hand-to-hand contact, by touching a contaminated surface or by being spewed through the air in droplets as someone sneezes, coughs or talks. On average adults get about two to four colds a year, children about six to 10, mostly in the fall and winter months. And every year 5 to 20 percent of the population comes down with the flu, according to the Centers for Disease Control and Prevention, with about 200,000 people getting sick enough to be hospitalized.

“The difference between the common cold and flu is the severity of fever,” said Jeff Dimond, a spokesman for the CDC. “The flu is usually accompanied with fever, aches and pains, and congestion in the lungs. A cold is more in your head. Both are contagious,” often before symptoms even show up.

Colds linger for a week to 10 days. The flu is shorter but carries a bigger wallop. It tends to clear up after two to five days, but sufferers may feel drained and exhausted for another week.

Want to avoid all this?

Here are a few simple tips for staying healthy this season from the experts (CDC, doctors, infectious-disease researchers).

Germ warfare

The No. 1 preventive measure for killing germs is washing hands, said Dimond.

“If you think about where you put your hands, you wipe your nose then touch the elevator,” Dimond said. “A virus can last for six hours on those elevator buttons. If you have bowls of nuts or M&Ms out and everybody is dipping their hands into it, germs get passed around.”

Not very appetizing? The CDC recommends washing hands, both tops and palms, for about 20 seconds with soap, then rinsing. Wash before eating and preparing food. Wash after using the bathroom, blowing your nose, changing a diaper and caring for a sick person, to name a few common situations.

If washing your hands with soap is not doable, slather on hand sanitizer, Dimond said. “Part of working here at the CDC [in Atlanta], we are highly aware of hand hygiene,” he said. “At every floor there is a hand sanitizer and a big sign at the front door to wash hands.”

Secretions from your nose are often clear in the beginning of a cold and thicken as the cold progresses, said Ann Rixinger, an infectious-disease specialist in Annandale. “But be careful not to wipe your eyes, as germs can go into tear ducts and then get in the lymphatic system,” she said. “We will assume no one picks their nose. For little kids we have to teach good hygiene, using tissues and keep extra containers of Purell around.”

Stay away from Dracula

Steer clear of anyone sneezing, blowing his nose or coughing, or at least give such people a wide birth of at least six feet, Rixinger said. “People should cover their mouth when they cough and sneeze,” she said. If you have an office mate or child who does not cover up when coughing or sneezing, encourage him or her to do so.

But not into hands. Do it into a tissue or into your elbow, raised to block the spew — “the Dracula cough,” Dimond explained. “It is common sense and common courtesy.”

And you should try to stay home from work or school “if you are coughing and wheezing [because otherwise] in all probability you will pass that cold on to someone else,” Dimond said.

In addition to that, wipe surfaces — desks and tables, phones, steering wheels — with disinfectants and cleansers periodically.

No shot in the dark

The best protection against the flu virus is a yearly flu shot. This year’s strain is the same as last year’s, Dimond said, but if you had a flu shot last year, it is no longer effective for this season. So you’ll need a new shot. Getting a shot this season also helps ensure you won’t pass on the virus to those around you if you get infected.

Flu shots are plentiful this season, but get one soon since it takes several weeks to take full effect. “Each season is a discrete season,” Dimond said. “Last year we had a light flu season. We have no idea what to expect this year. There are 166 million doses of flu shots; it is easy to find; and it is safe and affordable.”

This year’s vaccine is made up of three flu viruses: The H3N2, remnants of H1N1 (the so-called swine flu) and the B strain of the flu. “So far, we’ve had light activity,” Dimond said. “The flu picks up after the holiday season. People go away, congregate and get on airplanes: That’s how the virus spreads.”

An ounce of prevention

Keeping your body healthy with a good diet, regular exercise and sleep will help guard against viruses, Rixinger said. “People who have stress get viruses and get more colds,” she said.

What about supplements?

Researchers have studied the effects of Vitamin C on colds for years. An Australian study in 2007, which reviewed 30 clinical trials, found that a Vitamin C supplement failed “to reduce the incidence of colds in the normal population,” which means “that routine mega-dose prophylaxis is not rationally justified for community use.”

A few studies — including one in Finland and another from Case Western Reserve University School of Medicine — suggest that zinc may be helpful, if taken at the first onset of a cold. How much and for how long has yet to be detemined. Taking too much zinc can cause problems, including fever, stomach pain and fatigue

And if you get sick . . .

“You can’t cure a cold,” Dimond said. It just has to run its course.

So by no means, he emphazised, should you take antibiotics for a cold. “Antibiotics do not work,” he said. “If you take those drugs for those viruses, you build up antibiotic resistance, and if it is something else, you create a bigger health problem down the line.”

He recommends an over-the-counter antihistamine and pain relievers for aches and head congestion. “Everybody has his or her own medication of choice,” he said. “One person told me to put Vicks VaporRub on the bottom of your feet and wear socks to bed. I have no idea if that works.”

And it turns out, your grandmother was right about chicken soup and gargling. Both use a fair amount of salt, which works as an anti-inflammatory and mucus-thinning agent.

“You feel better with more salt, and your blood pressure feels better,” Rixinger said. “Chicken soup is a good source of sodium, and it goes down easily.”

Otherwise, you just need to wait it out. And when you get back to work with the remnants of a cough, please, cover your mouth.

Hambleton is a Washington-based freelance writer and documentary filmmaker.