Vaccine Administration Guidelines

Pre-Vaccination Screening

The Centers for Disease Control and Prevention (CDC) recommends verifying the absence of contraindications, including no history of anaphylactic reaction to vaccine components, before administering the vaccine 1
The CDC and the Advisory Committee on Immunization Practices (ACIP) recommend prioritizing vaccination for susceptible individuals, including healthcare workers, teachers, childcare employees, and household contacts of immunocompromised persons 1, 2, 3
Contraindications for varicella vaccine administration include pregnancy, severe immunocompromise, high-dose systemic steroids, and severe allergies to vaccine components, as stated by the CDC and supported by the American Academy of Pediatrics (AAP) and ACIP 4, 2, 5

A two-dose varicella vaccine series is recommended for adults without a history of chickenpox, administered 4-8 weeks apart, to prevent severe disease and complications 1
The recommended vaccine type is single-antigen varicella vaccine, with a dosage of two 0.5-mL doses administered subcutaneously, given 4-8 weeks apart 1
A two-dose varicella vaccination schedule provides optimal protection, with a significantly higher protection rate of 98.3% compared to a single dose of 85% efficacy, as reported by the CDC and supported by the AAP and ACIP 1
The following table summarizes the vaccine efficacy:
Dose Efficacy
1 dose 85%
2 doses 98.3%

Dose	Efficacy
1 dose	85%
2 doses	98.3%

HIV-infected individuals with a CD4 count ≥200 cells/μL who previously received 1 dose should consider completing the 2-dose series, while those with asymptomatic or mildly symptomatic HIV infection and a CD4 T-cell count ≥200 cells/mm³ can receive the vaccine 6, 4, 2
Primary immune deficiency disorders without defective T-cell-mediated immunity can receive the vaccine, according to the CDC 4
Patients planning to start immunosuppressive therapy should receive the vaccine ≥4 weeks before initiating therapy, as recommended by the CDC 4
Leukemia patients in remission should only be vaccinated with expert guidance and availability of antiviral therapy, and patients receiving <2 mg/kg or <20 mg/day of prednisone (or equivalent) may be vaccinated, as stated by the CDC 1

Breakthrough varicella after vaccination is typically milder with fewer lesions, and the second dose of varicella vaccine contributes to community immunity, helping prevent outbreaks in school and other congregate settings 1
Serologic testing to verify immunity is generally neither necessary nor recommended before vaccination if a person lacks other acceptable evidence of immunity, according to the AAP 3
Postimmunization serologic testing is not recommended as commercial assays may not be sensitive enough, according to the AAP 3
If the individual has a history of typical varicella disease verified by a healthcare professional, vaccination may not be necessary, as stated by the AAP 3