Varicella Vaccination for a 14-Year-Old
A 14-year-old adolescent needs two doses of varicella vaccine administered at least 4 weeks apart if they have not previously been vaccinated or lack evidence of immunity. 1, 2
Vaccination Requirements for Adolescents
For adolescents aged 13 years and older (including 14-year-olds):
- Two 0.5-mL doses of single-antigen varicella vaccine are required 1
- The doses should be administered subcutaneously 1
- The recommended interval between doses is 4-8 weeks 1, 2
- If more than 8 weeks elapse after the first dose, the second dose can still be administered without restarting the schedule 1, 2
Evidence of Immunity
Before vaccination, determine if the adolescent already has evidence of immunity, which includes:
- Documentation of 2 appropriately timed doses of varicella vaccine
- Laboratory evidence of immunity or laboratory confirmation of disease
- Healthcare provider diagnosis or verification of varicella disease
- Healthcare provider diagnosis or verification of herpes zoster 2
Vaccine Effectiveness
The two-dose regimen provides significantly better protection than a single dose:
- Two-dose regimen: 98.3% efficacy
- Single-dose regimen: 94.4% efficacy 3
- The risk for breakthrough disease is 3.3-fold lower among those who received 2 doses compared to those who received only 1 dose 3
Important Considerations
- Only single-antigen varicella vaccine should be used for persons aged ≥13 years, as MMRV (combination measles, mumps, rubella, and varicella) vaccine is not licensed for use in this age group 1, 2
- Varicella disease can be more severe in adolescents and adults, making vaccination particularly important 1
- If the adolescent previously received one dose of varicella vaccine, they still need a second dose with at least 4 weeks between doses 1, 2
Catch-up Vaccination
Studies show that catch-up vaccination campaigns have been successful, with coverage of two or more doses increasing from 3.6% to 56.7% in 16- to 17-year-olds between 2007 and 2014 4. However, missed vaccination opportunities remain common, with 77% of one-dose vaccinated adolescents having one or more missed opportunities to receive their second dose 4.
Contraindications
The varicella vaccine should not be given to adolescents who are:
- Pregnant or considering pregnancy within 1 month of vaccination
- Immunocompromised
- Have severe allergies to vaccine components 1
By ensuring proper two-dose vaccination of adolescents against varicella, we can significantly reduce their risk of disease and its complications, as well as decrease transmission in school settings.