From the Guidelines
The Centers for Disease Control and Prevention (CDC) recommends varicella vaccination for all children, with the first dose administered at 12-15 months of age and a second dose at 4-6 years of age 1. For individuals 13 years of age and older who have not been vaccinated, two doses of varicella vaccine should be administered at least 28 days apart for people 13 years of age and older without evidence of immunity, as defined in the “Recommendations” section of this report 1.
Key Points
- The varicella vaccine is administered subcutaneously in two 0.5-mL doses, separated by at least 3 months for children and at least 28 days for individuals 13 years of age and older 1.
- A second dose of varicella vaccine is necessary to provide evidence of immunity for people who previously received only one dose of varicella vaccine 1.
- The CDC recommends routine vaccination of all healthy persons aged >13 years without evidence of immunity 1.
- Varicella vaccination is also recommended for outbreak control, and persons who do not have adequate evidence of immunity should receive their first or second dose as appropriate 1.
- Health-care personnel without evidence of varicella immunity should be excluded from duty unless they receive the second dose of varicella vaccine within 3-5 days after exposure 1.
From the Research
CDC Guidelines for Varicella (Chickenpox)
The Centers for Disease Control and Prevention (CDC) guidelines for Varicella (chickenpox) are based on several studies that have evaluated the effectiveness of varicella vaccination.
- The CDC recommends a routine second dose of varicella vaccine for children at age 4-6 years, in addition to the first dose given at age 12-15 months 2.
- A study published in 2011 found that the effectiveness of 2 doses of varicella vaccine was 98.3% (95% confidence level: 83.5%-100%; P < .001) 3.
- Another study published in 2014 found that two-dose varicella vaccination coverage among children aged 7 years increased from a range of 3.6%-8.9% in 2006 to a range of 79.9%-92.0% in 2012 2.
- The CDC also recommends vaccination requirements for child care and school entry, and for postexposure, as well as vaccination of susceptible adults 4.
- A 10-year follow-up study published in 2019 found that two doses of combined measles-mumps-rubella-varicella vaccine provided optimum long-term protection for the prevention of varicella, with a vaccine efficacy of 95.4% (95% CI: 94.0-96.4) 5.
- The impact of the US two-dose varicella vaccination program on the epidemiology of varicella outbreaks was evaluated in a study published in 2015, which found that the program significantly reduced the number, size, and duration of varicella outbreaks in the US 6.
Key Findings
- Two doses of varicella vaccine are highly effective in preventing varicella disease 3, 5.
- The CDC recommends a routine second dose of varicella vaccine for children at age 4-6 years 2.
- Varicella vaccination coverage has increased significantly since the introduction of the two-dose vaccination program 2.
- The two-dose varicella vaccination program has significantly reduced the number, size, and duration of varicella outbreaks in the US 6.