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Despite all the research, everyone of us catches cold and most of us catch frequently Our failure to control one of the commoned of all ailments surgery and has rid whole countries of such killing diseases as Typhon and the Plague Put the problem of common cold is usually difficult and my has yet to be done to solve it It is known that cold is caused by one of a number of viral infections that affect the lining of the nose and other passages leading to the lungs but the confusing variety of viruses makes its study and remedy very difficult. It was shown in 19-0 that many typical colds in adults are caused by one or the other of a family of viruses known as thinovinmes, yet there still remain many colds for which no virus has as yet been isolated There is also the difficulty that because they are so much smaller than the bacteria which cause many other infections, viruses cannot be seen with ordinary microscopes. Nor can they be cultivated easily in the bacteriologis's laboratory, since they only grow within the living cells of animals or plants. An important recent step forward, however, is the development of the technique of tissue culture, in which bits of animal tissue are enabled to go on living and to multiply independently of the body. This has greatly ided virus research and has led to the discovery of a large number of viruses.Their existence had previously been not only unknown but even unsuspected.

The fact that we can cold repeatedly creates another difficulty .