How does blog virus effect a blog?

First of all you have to learn that what is a virus . A computer virus is a program which can be load in your computer , blog or server . In that condition your blog runs against your wishes .Your blog or your computer is controlled by the virus code. Viruses can also replicate themselves .
What a virus can do
A virus can do everything which is bad for your blog .
  • It can delete your blog's post or other data.
  • It can share your admin information to others
  • Virus can share your visitor's data to the hacker who insert the virus in your blog or computer
  • Can remove your blog configuration info partially of completely .
  • An virus infected blog's ranking is also drooped suddenly by the search engine