There are many causes of thrombocytopenia. Your doctor may tell you that you have a form of the condition called immune thrombocytopenia (ITP), which is one of the most common causes of low platelets in people who do not have symptoms. You may hear it referred to by its old name, idiopathic thrombocytopenic purpura.
How the chickenpox vaccine works. The chickenpox vaccine is a live vaccine and contains a small amount of weakened varicella zoster virus. The vaccine causes your immune system to produce antibodies that will help protect against chickenpox. Read more about live vaccines. Read more about chickenpox vaccine side effects.
Live virus vaccines use the weakened (attenuated) form of the virus. The measles, mumps, and rubella (MMR) vaccine and the varicella (chickenpox) vaccine are examples. Killed (inactivated) vaccines are made from a protein or other small pieces taken from a virus or bacteria. The flu vaccine is an example.