Before we can receive a vaccine it takes many years of research and testing to develop it.
According to the Centers for Disease Control and Prevention it can take between 10 and 15 years of research and testing before a vaccine is available to the public.
The CDC said the first stage in creating a vaccine is for scientists to develop an antigen that can prevent a disease. Once the initial vaccine is created it has to be cleared by the U.S. Food and Drug Administration for more investigation. According to the CDC, at least three more intense clinical trials over the course of several years are conducted to ensure the vaccine is effective and to determine dosage. Researchers also watch for any side effects.
In the final phase of testing the vaccine is given to a large test group of tens of thousands of human volunteers, according to the CDC.
If the vaccine passes all of the test phases it will await FDA approval. Once this approval is obtained the FDA will ensure the vaccine is safe by testing it and monitoring its production facilities, according to the CDC and the FDA. The FDA says it also monitors the vaccine long-term to document any reactions to the vaccine.