What are Viruses?

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What are Viruses?

Viruses are organisms that are even smaller than bacteria. Although the size of viruses varies the thickness of an average human hair is approximately 1000 times bigger than a virus. See the SMAC report for more details. Viruses consist of just a string of genetic material (DNA) that is contained by a shell known as the 'viral coat'. They are not cells and they border on being non-living infectious agents as they are only active when in a host cell. Viruses can only replicate (produce more viruses) using the machinery of the cell. This could be a bacterium, plant cell or human cell depending on the type of virus.

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Date of Posting: 09/01/2003
Date of next Review: 13/01/2005

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