Risk Factors for Shingles Recurrence
The most significant risk factor for shingles recurrence is immunocompromised status, particularly HIV infection, which increases recurrence risk 20-100 fold compared to immunocompetent individuals. 1, 2
Primary Risk Factors
Immunosuppression
- HIV infection and AIDS represent the highest risk, with immunocompromised patients experiencing recurrence rates of 0.0-18.2% and incidence rates of 17.0-55 cases per 1000 person-years, compared to 1.2-9.6% recurrence and 1.7-16.6 cases per 1000 person-years in immunocompetent populations 3
- Chronic corticosteroid use significantly increases reactivation risk by suppressing cell-mediated immunity 1, 2
- Active malignancies and chemotherapy treatment create conditions for viral reactivation 4, 1
- Organ transplant recipients on immunosuppressive medications face elevated recurrence risk 3
Demographic Factors
- Female sex is independently associated with higher recurrence rates 3
- Advanced age increases risk, as cellular immunity to varicella-zoster virus naturally declines with aging 4, 5
- Family history of herpes zoster predisposes individuals to recurrence 3
Clinical Characteristics of Initial Episode
- Long-lasting pain after the initial shingles episode (particularly postherpetic neuralgia) correlates with increased recurrence risk 3
- Herpes zoster ophthalmicus (eye involvement) may predispose to future episodes 3
Comorbid Conditions
- Diabetes mellitus increases susceptibility to recurrence 3
- Conditions causing decline in cellular immune response create vulnerability for viral reactivation 4
Modifiable Risk Factors
Physical and Psychological Stress
- Hard work and physical exhaustion can trigger reactivation 4
- Psychological stress may compromise immune surveillance of latent virus 6
Environmental Triggers
- Ultraviolet light exposure can precipitate reactivation 6
- Fever from other illnesses may trigger episodes 6
Important Clinical Caveats
No drug has been proven to prevent shingles recurrence in any population, including HIV-infected persons, according to multiple USPHS/IDSA guidelines 6. This represents a critical gap in preventive therapy.
However, the CDC recommends recombinant zoster vaccine (Shingrix) for all adults aged 50 years and older, regardless of prior shingles episodes, to prevent future recurrences 7, 8. This vaccination strategy is the only evidence-based preventive measure currently available.
For patients with frequent or severe recurrences, daily suppressive antiviral therapy may be considered: acyclovir 400 mg orally twice daily, famciclovir 250 mg orally twice daily, or valacyclovir 250 mg-1000 mg daily 7. The CDC documents safety of acyclovir for up to 6 years of continuous use and recommends reassessing need for suppressive therapy after 1 year 7.
Recurrence is generally uncommon in immunocompetent individuals but cannot be entirely prevented once someone has had an initial episode, as the virus remains latent in dorsal root ganglia indefinitely 7, 4.