Interestingly enough, despite the billions of colds the human race has suffered through, researchers still aren't completely sure how colds are usually transmitted. But most specialists now believe that the two most common modes of transmission are by hand contact and through the air.
Some researchers tend to favor the aerosol theory of transmission -sneezing can send a blast of rhinoviruses 3 feet or more. But two cold researchers at the University of Virginia School of Medicine in Charlottesville, M.D, have convincingly demonstrated a sort of nose-to-hand-to-nose theory of transmission.

In one experiment, Dr.and Dr. had 15 college students lather their hands with the nasal secretions of people with colds, then touch their noses or eyes. Result: 11 ofthE' 15 got a cold. By contrast, out of 12 students who just sat at a table with cold sufferers, only 1 got sick. Hence, this general theory:

People with colds, whose hands are swarming with cold viruses from blowing their noses, touch a doorknob or another person's hand and in this way spread the virus to a fresh victim's hand. That person, in turn, gets infected when their hand travels to their own nose or eyes. (The researchers secretly observed doctors at conferences and noted that they touched their noses or eyes on average about once every 11/2 hours.)

How to break this chain of transmission? In another experiment, Dr. Gwaltney and Dr. Hendley had mothers dip their hands in a dilute iodine solution - which kills rhinoviruses for up to 2 hours-when any family member got a cold. Result:

They got sick less than half as often as mothers who didn't sterilize their hands. These research findings translate into a couple of simple ways for you and your sex partner to protect each other. When your partner has a cold, wash your hands frequently and try to keep your hands away from your nose and eyes. Remember to wash your hands (or, preferably, shower) after sex or other close contact.

To protect your mate when you've got a cold, always cover your mouth when you sneeze, and use disposable tissues rather than cloth handkerchiefs, which are rather like swaddling clothes for cold viruses (they can live for hours in there).