Great question Erika, yes there are medicines which can be used to treat viruses although our immune systems are pretty good at doing that job but sometimes we need extra help. Tamiflu is one anti-viral medicine that some people have heard of as it was a medicine every one wanted to get their hands on back in 2009 when there was a flu pandemic. A pandemic is an outbreak of disease which affects a lot of people and can cause a lot of deaths. Flu is caused by the influenza virus, which is a very clever virus and can change itself easily -that’s reason why we have to get a new variety of flu vaccine every flu season (each year from Sept on).
Vaccines are amazing as they can allow our own immune systems to develop cells and proteins that can fight and destroy viruses. We can use vaccines to protect against more than just viral infection but we have a virus to thank for educating us on vaccination and our immune system in the first place…have a google for cowpox and Edward Jenner to learn more about this or see this nice website produced by Irish scientists in Cork; http://microbemagic.ucc.ie/about_microbes/good_viruses.html.
Hope that helps….thanks for your interest in viruses.