Volume :
3
Issue :
1
Abstract :
A virus is a biological agent that reproduces inside the cells of living hosts. The virus attaches to a cell enters it, and releases its DNA or RNA inside the cell. The viruses DNA or RNA is the genetic material containing the information needed to replicate the virus. When inflected by a virus, a host cell is forced to produce many thousands of identical copies of the original virus. The infected cell usually dies because the virus keeps it performing its normal functions. When it dies, the cell releases new virus which go into infect other cell. Viruses spread in many different ways. Influenza are spread through air, Norovirus are transmitted through faecal oral route, contaminate hands, food and water. Rotovirus are spread by direct contact with infected children. HIV transmitted during sex. Usually the viruses are eliminated by immune system. Antiviral drugs are one class of antimicrobials and it may interfere with the reproduction of viruses or strengthen the immune response to the viral infection.