A systematic review and meta-analysis of herpes zoster occurrence/recurrence after COVID-19 infection and vaccination

To inform surveillance, prevention, and management strategies for the varicella zoster virus (VZV) during the COVID-19 pandemic, this study aimed to evaluate the risk of herpes zoster (HZ) occurrence/recurrence following COVID-19 infection and vaccination. A comprehensive search across seven databases was conducted up to January 31, 2024, to identify studies relevant to the occurrence of HZ following COVID-19 infection and vaccination. The meta-analysis included five studies on postinfection HZ and 13 studies on postvaccination HZ. Patients infected with COVID-19 had a 2.16-fold increased risk of HZ (95% confidence interval [CI]: 1.24-3.76) than uninfected individuals. However, there was no significant association between COVID-19 vaccination and the risk of HZ compared to controls, with a relative risk (RR) of 1.08 (95% CI: 0.84-1.39). Furthermore, a descriptive analysis of 74 postinfection and 153 postvaccination HZ studies found no significant differences on gender or age (<50 and ≥50 years) following COVID-19 infection. Notably, 44.0% of the HZ cases postinfection appeared within the first week, with 69.5% resolving within 10 days, predominantly presenting as skin lesions. In the postvaccination group, the majority (60.1%) developed HZ after the first dose and 66.7% occurred within 1 week. Moreover, 44.6% resolved within 10 days and 50.0% within a month, primarily exhibiting skin lesions and postherpetic neuralgia. The study found that COVID-19 infection increases the risk of HZ, but the COVID-19 vaccine does not. Further study is needed to explore the association between COVID-19 and HZ.