Re: how are vaccines bad for you?
Yes, the environment is full of viruses and bacteria, most of which can be controlled by a normal functioning immune system.
A few, however, cause dangerous problems or even death before the immune system can control or destroy them (e.g. polio - paralysis, rubella in pregnant women - birth defects, etc.). And you will get sick and shed infectious virus or bacteria by coughing all over the place, etc., even if you do avoid long term effects.
A vaccine shows your immune system a weak or dead virus or bacteria so that it learns to recognize it so that it reacts more quickly and controls or destroys a wild type infection before it can do any damage to you. And you won't be shedding infectious virus or bacteria because you won't be coughing all over the place, etc..