Polio is one of the deadliest virus to date, why, because the virus will slowly kill it's host away by suffocating it. What the virus will do is it will enter through your mouth and then start to replicate itself like all viruses. It will then clog up your wind pipe, slowly suffocating you to death. One thing that made it so deadly, was that it was so easy to catch. The virus was airborne and would spread very quickly. There was soon a vaccine that would help your immune system fight back against the virus. 1 out of 100 times the the vaccine wouldn't work. But before the vaccine was invented, there was an invention that would help the host of polio survive. These were called the iron lungs. You would put your body (except you head) in the machine and it would help your lungs to breath. -----------To make all the shots before winter rolls around, they will start making shots in the early summer. This is not the most effective way, but is really the only. This is were the universal vaccine comes in. The vaccine would be able to fight off every type of flu. The product is still in the works, but is predicted to hit the market as little as 5 year.----------Bacteria is a single celled microorganism that usually enters through your mouth. Bacteria can survive in multiple types or environments and will give you things such as strep throat or tuberculosis. A virus is much smaller than bacteria and needs a living host to reproduce. Unlike bacteria, viruses can enter your body in versus ways. What the virus will do is it will highjack your body and reprogram your cells to start reproducing the virus. They can give you symptoms such as chicken pox and most famously, types of colds.----------Zika is a virus that is spread by an Aedes species mosquito. If you're unlucky enough to get bitten, these are some possible symptoms; Fever, rash, headache, joint pain, red eyes, and or muscle pain. For females it may have brith effects to their baby(ies). Some ways to try to prevent zika is to wear long sleeved shirts and pants, put on bug spray, and if needed to hang up mosquito nets.