Epidemiology and costs of herpes zoster: background data to estimate the impact of vaccination.

In 2004, we conducted a study in Piemonte (Italy), in order to describe incidence, treatment, hospitalizations and costs of herpes zoster (HZ), in population over 14 years of age. Twenty-four regional general practitioners, with 26,394 patients >14 years in charge (0.71% of the regional population), reported prospectively all diagnosed HZ cases. In addition, all regional hospital discharge records were reviewed. Forty-six HZ cases treated at home were reported, accounting for a total incidence of 1.74 cases/1000 population >14 years per year. HZ rate standardized by age on regional population 14 years older is 1.59/1000. The cost per observed home case was 136.06 euros. The incidence of hospital admissions was 0.12/1000 inhabitants. The mean cost of hospitalized cases was 4082.59 euros. These results contribute to depict the impact of HZ in the general population, and to provide background data for setting-up either mathematical models aimed to estimate the impact of vaccination on HZ, and the cost-benefit analyses of various preventive and therapeutic scenarios.