Emma+FLU+notes

3 reasons to get your flu vaccine 1. prevents influenza related death 2. prevents severe illnesses 3. protects other people -Especially young children and the elderly who don't have strong immune systems

How a virus takes over: All viruses only exist and make more viruses. And with the possible exception of bacterial viruses which kill harmful bacteria, all viruses appear to be harmful because their replication leads to the death of the cell which the virus entered. A virus enters a cell by first attaching to a specific structure on the cell's surface via a specific structure on the virus surface. Depending on the virus, either the entire virus enters the cell, or perhaps only the genetic material of the virus is injected into the cell. In either case however, the ultimate result of viral infection is the exposure of virus genetic material inside the entered cell. Then, the virus material essentially "takes over" the cell and nothing but viral parts are made, which assemble into many complete viruses. These viruses are mature and leave the cell either by a process called "budding" (just one or a few viruses at a time leave the cell) or by a process called //lysis// (the cellular membrane ruptures and releases all of the virus particles at once).

Influenza viruses are found in MANY different animals