What are the recommendations for shingles vaccination in adults aged 50 years and older, including those with weakened immune systems or a history of shingles?

Shingles Vaccine Recommendations

Primary Recommendation for Adults ≥50 Years

All adults aged 50 years and older should receive the 2-dose Shingrix (recombinant zoster vaccine, RZV) series, administered intramuscularly with the second dose given 2-6 months after the first dose, regardless of prior shingles history or previous Zostavax vaccination. 1

Standard Dosing Schedule

• First dose: Administer immediately upon reaching age 50 1
• Second dose: Give 2-6 months after the first dose (minimum interval: 4 weeks) 1
• If the second dose is delayed beyond 6 months: No need to restart the series; simply complete with the second dose 1

Vaccine Efficacy and Duration

• Efficacy against herpes zoster: 97.2% in adults aged 50+ years, maintained at >90% across all age groups 1, 2
• Efficacy against postherpetic neuralgia (PHN): 88.8% in adults ≥70 years 3
• Duration of protection: Sustained above 83.3% for at least 8 years, with minimal waning 1
• This represents dramatically superior protection compared to the older Zostavax vaccine, which declined to only 14.1% efficacy by year 10 1

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Special Population: Immunocompromised Adults

Age ≥19 Years Who Are Immunocompromised

Immunocompromised adults aged ≥19 years should receive Shingrix using a shortened schedule, with the second dose given 1-2 months after the first dose. 1, 4

Who Qualifies as Immunocompromised

• Hematologic malignancies (leukemia, lymphoma, multiple myeloma) 3
• Solid organ malignancies 3
• Solid organ or hematopoietic stem cell transplant recipients 1, 3
• HIV/AIDS 3
• Primary immunodeficiency disorders 3
• Chronic high-dose glucocorticoids (≥20 mg/day prednisone equivalent) 3
• Disease-modifying antirheumatic drugs (DMARDs), biologics, or JAK inhibitors 1, 5
• Any other immunosuppressive therapy 4

Critical Safety Note

Shingrix is the ONLY appropriate herpes zoster vaccine for immunocompromised individuals—the live-attenuated Zostavax is absolutely contraindicated in this population due to risk of disseminated VZV infection. 1, 3

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Vaccination After Prior Shingles Episode

Administer Shingrix once acute symptoms have resolved, typically waiting at least 2 months after the episode, as having shingles once does not provide reliable protection against future episodes (10.3% cumulative recurrence risk at 10 years). 1

• Natural immunity from a prior shingles episode is insufficient to prevent recurrence 1
• Vaccination reduces recurrence risk significantly 1
• The 2-month waiting period allows for complete symptom resolution and immune system recovery 1

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Revaccination for Those Who Previously Received Zostavax

All adults who previously received Zostavax should receive the full 2-dose Shingrix series, with the first dose given at least 2 months after the last Zostavax dose. 1

Rationale for Revaccination

• Zostavax efficacy wanes dramatically over time (14.1% by year 10) 1
• Shingrix provides superior and sustained protection (>90% efficacy maintained for 8+ years) 1
• Real-world data shows revaccination with Shingrix after prior Zostavax lowered herpes zoster incidence from 7.54 to 2.39 per 1000 person-years 1
• Do not delay revaccination—there is no maximum interval after previous Zostavax, and waiting serves no purpose while leaving the patient vulnerable 1

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Timing Considerations with Other Vaccines and Medications

Concurrent Vaccination

• Shingrix can be administered simultaneously with inactivated influenza vaccines without any required waiting period 1
• No spacing interval is required between Shingrix and other inactivated vaccines 1

Vaccination During Acute Illness

• Wait until acute flu symptoms (fever, severe malaise, myalgias) have resolved before administering Shingrix 1
• No specific waiting period is required after influenza illness resolves 1

Timing with Immunosuppressive Medications

For patients starting JAK inhibitors (e.g., tofacitinib):

• Optimal approach: Complete the full 2-dose Shingrix series BEFORE starting tofacitinib to maximize immune response while not yet immunosuppressed 1
• If urgent tofacitinib initiation is required: Administer at least the first Shingrix dose before starting therapy, then complete the second dose 1-2 months later (though immune response may be somewhat reduced) 1
• Never use live-attenuated Zostavax in patients on or about to start JAK inhibitors—only Shingrix is appropriate 1

For patients on chronic glucocorticoids:

• Shingrix can be safely administered to patients on low-dose glucocorticoids (<10 mg/day prednisone equivalent) without adversely impacting vaccine response 1
• Studies show only mild disease flares (4-17%) after Shingrix vaccination in patients with autoimmune conditions, with no serious adverse events 1

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Adults Under Age 50: When to Vaccinate Early

Shingrix is NOT routinely recommended for immunocompetent adults under age 50, even with prior shingles history. 1, 5

Exception: Immunocompromised Adults Aged 18-49 Years

The ONLY indication for Shingrix before age 50 is for adults aged ≥18 years who are or will be immunocompromised. 5, 3, 4

Important Caveat for Those Without Chickenpox History

• Most adults (88-91%) have been exposed to VZV even without recalled chickenpox, making them capable of developing shingles 5
• If VZV serology confirms a patient is truly seronegative, they should receive the 2-dose varicella vaccine series (4 weeks apart) instead of Shingrix 5
• Shingrix is not indicated for prevention of primary varicella (chickenpox) 3

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Common Side Effects and Safety Profile

Expected Adverse Reactions

• Injection-site reactions (pain, redness, swelling): 9.5% experience grade 3 reactions vs. 0.4% with placebo 1
• Systemic symptoms (myalgia, fatigue, headache): 11.4% in vaccine recipients vs. 2.4% in placebo recipients 1
• Most adverse reactions are transient and mild-to-moderate, resolving within 4 days 1, 2

Safety in Special Populations

• No serious safety concerns identified in large clinical trials, with similar rates of serious adverse events between vaccine and placebo groups 1
• In autoimmune disease patients, mild disease flares can occur (4-17%) but without serious adverse events 1
• No statistically significant increase in autoimmune disease flares following vaccination in large database studies 1

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Key Clinical Pitfalls to Avoid

• Never use Zostavax in immunocompromised patients of any age—only Shingrix is safe and appropriate 1, 3
• Do not delay Shingrix vaccination to conduct varicella serology in immunocompetent adults aged ≥50 years 5
• Do not confuse the waiting period after an acute shingles episode (2 months) with the interval between vaccine doses (2-6 months) 1
• Do not assume absence of recalled chickenpox means VZV-seronegative status—most adults have been exposed even without clinical disease 5
• Do not administer Shingrix during neutropenic periods if avoidable—consider timing between chemotherapy cycles (>7 days after last treatment) when feasible 1

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No Booster Doses Required

No additional booster doses beyond the initial 2-dose series are currently recommended by any guidelines, including those from the American College of Physicians. 1