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Contrary to popular belief,colds are not caused by exposure to severe weather.Colds are caused by viruses inside,and you're safer when skiing or even waiting for the bus on a snowy day than you are in a warm room, surrounded by friends,co-workers,or fellow students,who just may be passing the viruses around.If you feel a chill,you're already sick.A chill is an early sign:It's the cold that causes the chill,not the other way around.
While the virus can spread through air when a cold-sufferer coughs or sneezes,surprisingly,this is not the most common route of transmission.Numerous studies have now shown that the majority of colds are“caught”by hand contact.A cold-sufferer rubs her nose,thereby transferring the virus to her hand.Then a friend comes to visit.“Don't kiss me,”she warns,so the friend steps back and presses her hand.The friend then wipes her own nose or eyes,and several days later is stricken with a cold.Or parents pick up their child's used tissues and carefully throw them away,but fail to wash their hands afterwards.
Cold viruses also can be transferred to objects—telephones,towels,plates—and remain infectious for up to three hours.Frequent hand-washing—on the part of the cold-sufferer as well as other members of the household— will minimize the spread of viruses.
1. What can cause colds according to the passage?
