Management and prevention of herpes zoster: A Canadian perspective

Abstract

Varicella-zoster virus reactivation leads to herpes zoster - the main complication of which is postherpetic neuralgia (PHN). Rapid antiviral therapy initiated within 72 h of rash onset has been shown to accelerate rash healing, reduce the duration of acute pain and, to some extent, attenuate the development and duration of PHN. Other adjunctive therapies such as analgesics, antidepressants and some anticonvulsants are frequently required in the management of severe PHN. A live, attenuated zoster vaccine has been recently shown to significantly decrease herpes zoster incidence, PHN and the overall burden of illness when administered to adults older than 60 years of age. This new prophylactic modality has been reported to be cost-effective in the Canadian context, especially in the 60- to 75-year-old age group.

Keywords: Antivirals; Postherpetic pain; Prevention; Vaccine; Zoster.

Figures

Figure 1)

Cell-mediated immunity and development of herpes zoster (reproduced with permission from reference 1). Varicella is the primary infection caused by varicella-zoster virus (VZV), and its resolution is associated with the induction of VZV-specific memory T cells (blue line). Memory immunity to VZV may be boosted periodically by exposure to varicella or silent reactivation from latency (red peaks). VZV-specific memory T cell levels decline with age. The decline below a threshold (dashed green line) correlates with an increased risk of zoster. The occurrence of zoster, in turn, is associated with an increase in VZV-specific T cell levels. The administration of zoster vaccine to older persons may prevent VZV-specific T cell levels from dropping below the threshold for zoster occurrence (dashed blue line)

Figure 2)

Incidence rate of herpes zoster by age group per 10,000 population in British Columbia from 1994 to 2003 (adapted with permission from reference 8). yrs Years

Figure 3)

Number and rate of physician visits for herpes zoster in British Columbia, 1994 to 2003 (reproduced with permission from reference 8)

Figure 4)

Initial management of herpes zoster (adapted with permission from references and 60)