A virus can infect another virus

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Viruses can catch colds
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Viruses are glorified scraps of genetic code that are exquisitely designed to pirate a host to reproduce: the common cold virus needs cells in the nose and respiratory tract to reproduce, before being spread with a sneeze.
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But the discovery of a giant virus that itself falls ill through infection by another virus seems to suggest they too are alive, highlighting how there is no watertight definition of what exactly scientists mean when they refer to something as "living".
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A genetic study of ocean water has revealed an abundance of genetic sequences closely related to giant viruses, leading to a suspicion that they are a common parasite of plankton.
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Also my Win95 got some viruses, but it was not ALIVE (it was making practical jokes sometimes, like refuse to switch off and stuff, but I'm sure it wasn't alive!) :D

For an interesting definition of being alive:
autopoiesis (term introduced by Chilean biologists Humberto Maturana and Francisco Varela)

Article here.