What are viruses?
These midget microbes which attack plants and animals were first discovered in 1892. They were named viruses from the Latin word for poisons. Since they were too, small to be photographed, scientists spent a lot of time wondering whether they were living things or merely chemicals.
In the last few years, the powerful electron microscope has given us our first pictures of the viruses. Science can now see what they look like and study how they behave and multiply. Chemical analysis adds to this information. We know of what substances viruses are made. All this new information is leading to great victories in medicine. Scientists are learning to cope with first one, then another of these midget microbes.
Tho polio vaccine was developed from this new work in science. In the next few months, we are told, there may be an injection to save children from measles. Other studies show that 100 different viruses may cause the common cold and this research may soon free us from those winter sniffles.
There are many more new advances in the war against viruses. As the work progresses, science is sure to discover whether a virus is a plant or animal. At the moment, these mysteries seem less important than the job of learning to cope with these tiny germs and microbes.
Photographs show that viruses vary in size and shape, They measure one or two million to an inch. Chemical analysis shows that they are heavy molecules with shells of protein. A special compound inside the shell carries information about how more viruses can be made.
When a virus attacks a living cell, the protein shell is left outside. The compound inside the virus passes into the cell and orders the cell to make more viruses instead of doing its normal work. This is how these microbes destroy the cells of living tissue.
Viruses can be suspended in a clear liquid and kept inside a test tube. Nothing will happen. The tiny microbes spring into activity only when they get themselves inside a living cell of the kind they need. There they use materials belonging to the cell and begin to multiply. Since the scientists can now study these activities, they can test to see what chemicals will stop the viruses without damaging living cells.
Tile can expect great advances in medicine from this new research in viruses. other specialists are turning their microscopes on the viruses that attack the plant and animal world. The first virus discovered was a plant microbe. It caused the disease called tobacco mosaic. Foot and mouth disease is caused by a virus which attacks our farm animals.