Viruses and Bacteria are totally different.
I’m going to say that again, cos it is really, really important.
Viruses and bacteria are totally different.
Viruses are almost nothing. They are just a shell of protein with some genetic instructions inside. On their own, outside a cell, they are inert. They just sit there. They don’t breathe, they don’t replicate, they don’t eat, poo or communicate.
In order for a virus to do anything it needs a host cell (such as a human cell). Buttons, called receptors, on the virus shell help it enter a useful host cell. Once inside, it is the cell that translates the genetic instructions. Normally the instructions cause the host cell to replicate and spread the virus and the way the virus shows itself is that spread in action. So for example, the viruses that cause a cold (rhinoviruses) spread by being breathed in. They attach to nose cells and enter them to replicate. Their genetic code also makes the nose cells inflamed, which produces mucous (snot) and causes sneezing. The sneezing spreads the virus. Another type of virus is the herpes virus that replicates in skin cells and also makes those cells blister, giving a rash. Inside the blisters of the rash are lots of viruses that have replicated in the infected skin cells of their host. When those blisters touch someone else they spread and the virus’s genetic material is spread.
The body fights viruses by making little proteins called antibodies. Antibodies cling to the receptors on the virus shell to stop it gaining entry into a host cell. They also mark the virus so it can be spotted easily by other immune cells and eaten. Antibodies can, on the whole, be made quickly, effectively and in huge numbers, meaning that the body is normally pretty good at dealing with viruses. Which is good because most infections are caused by viruses.
Bacteria, on the other hand, are something else entirely.