Protection to infectious disease

No one can actually protect themselves from disease completely unless they don't ever come in contact with anyone or anything. We, as human beings come in contact with different type of bacteria and viruses everyday, and we don't know what we come in contact with and when to avoid it. The best way for us to avoid getting a infectious disease is to keep ourselves clean and have proper sanitation. The only way you can keep from getting infected is to use your common sense to not get in contact with it. For example, don't use a needle again if its have already been used, use a new one to avoid coming in contact with any other diseases or bacteria.