• Inside their cellular host, a virus can create a huge number of copies and spread the infection to other cells.
• Viruses may spread from person to person through the mist of droplets from your mouth every time you cough or sneeze.
• Some viruses spread through contact with other bodily fluids. Ebola virus spreads from contact with infected blood, feces, or vomit, and not through the air.
• Other viruses travel through an intermediary, like a mosquito, which then infects people by biting them.

Viruses cannot move or reproduce without the help of a host cell. When a virus finds a host, it can increase and spread quickly.

To find a host, viruses have receptors on their surfaces that match up with their ideal target cell. It then takes over the cellular machinery inside the host's ...