All vaccines go through a long and thorough process of development and testing before they are licensed for use. It can take as MUCH as 20 years for a vaccine to go from first concept to being licensed. Vaccines have to be tested on ADULTS and children separately before they can be used for different age groups; this is because vaccines that work in adults MAY not work so well in children. No vaccines are tested on children before they have been FULLY tested on adults. See our page on Testing and Monitoring for more information.

All vaccines go through a long and thorough process of development and testing before they are licensed for use. It can take as much as 20 years for a vaccine to go from first concept to being licensed. Vaccines have to be tested on adults and children separately before they can be used for different age groups; this is because vaccines that work in adults may not work so well in children. No vaccines are tested on children before they have been fully tested on adults. See our page on Testing and Monitoring for more information.