The varicella vaccination program usually involves the first dose of varicella vaccine at 12 to 18 months of age and the second dose at 4 to 6 years of age, so you can still get the varicella vaccine at age four. The varicella vaccination is the most effective way to prevent varicella-zoster virus infection and is indicated for children and adults with no history of chickenpox. Normally, the first dose is given at 12 to 18 months of age, and the second dose is given at four years of age. If the first vaccination is given at four years of age, the second vaccination needs to be given at least three months apart, and the second vaccination is completed within three to four years. Therefore, chickenpox vaccination can still be performed at the age of four years, but it is contraindicated for those who are allergic to the vaccine components and should be postponed during the period of disease infection. It is recommended that you visit a vaccination center for more detailed information on specific precautions.