Is there any type of disease that, over a length of time, can disappear without trace?

Question: Is there any type of disease that, over a length of time, can disappear without trace?
- Keywords:
  cure,
  disappear,
  disease
Asked by to Del on 14 Mar 2014. This question was also asked by .
- Adelle Thrower answered on 14 Mar 2014:
  
  Good question
  Humans have an immune system so we sometimes combat diseases and we wouldn’t even know we had them.
  In terms if mankind – due to the invention if the vaccine and over a long time we have managed to eradicate small pox. The last know case was in 1978. The only live small pox virus is now kept in a lab and lots of countries are discussing whether to kill it or not., but if so the disease will be gone for good!

Question: Is there any type of disease that, over a length of time, can disappear without trace?