The Burden of Herpes Zoster on Hospital Admissions: A Retrospective Analysis in the Years of 2015-2021 from the Abruzzo Region, Italy.

(1) Background: Herpes zoster (HZ) is a disease caused by the reactivation of the Varicella Zoster Virus (VZV). Clinical reactivation, herpes zoster, takes place in 10-20% of subjects who contracted the primary infection, with a higher risk of developing zoster increasing proportionally with age, especially after 50 years of age. HZ is a common clinical problem, particularly among patients aged over 50 years and immunocompromised patients. Immunocompromised patients and adults could present an atypical and more severe course. In addition, they are at greater risk of complications. For this reason, it is important to understand the real burden of the disease and to identify the subjects who are at higher risk of HZ and its complications, also to direct preventive strategies at the right targets. The aim of the present study is to analyze HZ-related hospitalization trends in Abruzzo in the period of 2015-2021. (2) Methods: Data related to hospital admissions were extracted from the hospital discharge records (HDRs) of the whole region, considering all admissions during the years of 2015-2021. The trends in hospital admissions and length of stay were evaluated and analyzed. (3) Results: A total of 768 hospital discharges with a diagnosis of herpes zoster were registered in Abruzzo during the 7-year study period. During the study period, an increasing trend was observed from the year 2015 to the year 2017, ranging from 8.19 cases/100,000 to 11.5 cases/100,000 (APC (Annual percentage change) +20.8%; 95%CI -2.3; 47.6). After the year 2017, a significantly decreasing trend was observed, reaching 5.46 cases/100,000 in the year 2021 (APC -18.4%; 95%CI -31.5; -12.0). Across the entire study period, an average annual percentage change (AAPC) of -7.0% (95%CI -13.0; -1.3) was observed. (4) Conclusions: Despite the trend of a reduction in hospitalizations, this study highlights that HZ continues to have a great impact on public health. So, it is important to update recommendations for the use of the already available HZ vaccine and to implement new strategies to increase awareness of the prevention of the disease.