Review Article
Rama Murthy Vadrevu
Abstract
Viruses are both living and non-living organisms; living when found inside the host cell as they proliferate and grow, whereas, on occasions when they do not find any host cell, they are inactive or in a dormant stage. The virus can replicate itself and their genetic material mostly consists of either DNA or RNA. Different viral species spread in different ways. For example, plant virus spreads from plant to plant by insects and other organisms, some viruses are spread by body fluids of humans: influenza virus spread by aerosol droplets when people sneeze or cough. HIV is transmitted through body fluids; Dengue is propagated by mosquito bite. SARS virus is a respiratory disease that is spread by animals and humans.