What is a simple, concise guide for adult shingles vaccination in Canada, including dosing of the recombinant zoster vaccine (Shingrix) and considerations for those previously vaccinated with Zostavax?

Shingrix Vaccination Guide for Canada

All adults aged 50 years and older in Canada should receive the recombinant zoster vaccine (Shingrix/RZV) as a 2-dose series given 2 months apart, regardless of prior Zostavax vaccination or previous shingles episodes. 1

Core Recommendations

Standard Adult Vaccination (Age ≥50)

• Two doses of Shingrix, administered 2 months apart (0 and 2 months) 2
• Strong recommendation for all adults ≥50 years without contraindications 1
• This is the preferred vaccine over Zostavax (live vaccine) due to superior and more durable efficacy 1

Previously Vaccinated with Zostavax

Give Shingrix regardless of prior Zostavax vaccination 1

• Ideally wait at least 1 year after Zostavax before giving Shingrix 1
• However, a minimum interval of 8 weeks is acceptable if needed 3
• Two full doses of Shingrix are required even with prior Zostavax 1
• The immune response to Shingrix is non-inferior in those previously vaccinated with Zostavax 2

After a Shingles Episode

Vaccinate with Shingrix even after having had shingles 1

• Wait at least 1 year after the acute shingles episode resolves 1
• Recurrence rates are substantial (10.3% at 10 years), justifying vaccination 3
• Two full doses required 1

Immunocompromised Adults (Age ≥18)

Shingrix is now strongly recommended for immunocompromised adults aged ≥18 years 4

• This includes those with:
  • Hematopoietic stem cell transplant recipients
  • Hematologic malignancies
  • Chronic conditions (COPD, diabetes)
  • Any immunosuppressive therapy 5, 4
• Give two doses at 0 and 1-2 months 2
• Vaccinate at the earliest opportunity, ideally before immunosuppression begins 5
• Efficacy demonstrated at 68.2% in transplant recipients and 87.2% in hematologic malignancies 2

Key Clinical Pearls

Timing Considerations

• No need to check VZV serology before vaccination - vaccinate regardless of prior varicella history 1
• Can be given concomitantly with influenza vaccine, PNEUMOVAX 23, or PREVNAR 13 without interference 2
• If not given simultaneously, no specific waiting period required between vaccines 2

Common Pitfalls to Avoid

• Don't use Zostavax as first-line - it has inferior efficacy that wanes significantly over time (only 14.1% efficacy at 10 years) 3
• Don't skip the second dose - single-dose efficacy is substantially lower than the 2-dose series 3
• Don't delay vaccination in immunocompromised patients - their HZ risk equals or exceeds that of immunocompetent adults ≥50 years 4
• Don't give Zostavax to immunocompromised patients - it's contraindicated as a live vaccine; only Shingrix is appropriate 1

When Zostavax May Be Considered

Only use Zostavax when Shingrix is:

• Contraindicated
• Unavailable
• Inaccessible 1

This is a discretionary (weak) recommendation and applies only to immunocompetent adults ≥50 years 1.

Cost-Effectiveness Context

Both vaccines are cost-effective compared to no vaccination, particularly in those aged 65-79 years, but Shingrix is more cost-effective than Zostavax 1. Economic analyses also support vaccination in high-risk immunocompromised groups 4.