Epidemiology and costs of herpes zoster: Background data to estimate the impact of vaccination
Introduction
Herpes zoster is a clinical manifestation caused by the activation of the varicella-zoster virus (VZV) which has remained latent in the ganglia and dorsal nerve roots after varicella infection. It is characterized by an eruption of groups of vesicles along the course of the nerve and may provoke chronic pain (postherpetic neuralgia (PHN)), especially in persons over 50 years of age. The estimated lifetime risk of developing herpes zoster in those exposed to varicella is between 10 and 30%, while the incidence and severity increase with advancing age and immunocompromising conditions [1], [2], [3], [4], [5].
The incidence of herpes zoster per 1000 person-years ranges between 1.2 and 4.8 [4]. Contrary to varicella, herpes zoster is not a notifiable disease in Italy, so that the only known figures are those derived from hospitalized cases, whence the absence of national surveillance data on the community incidence. A retrospective Italian study estimated the annual incidence in individuals ≥15 years of age to be 4.14 cases per 1000 population [6]. However, no Italian studies conducted to date have included epidemiologic and economic analyses that would permit estimation of the global impact of herpes zoster.
This study's objectives were to estimate the annual incidence of herpes zoster in individuals >14 years of age in the region of Piemonte and the hospitalizations rates for the disease, to describe the home care management of cases, and to calculate the cost of home care and hospital care based on the Italian National Health Service (NHS) reference costs.
Estimation of zoster incidence also constitutes an initial step in building mathematical models for calculating the impact of varicella vaccination interventions that take zoster reactivation into account. In fact, several mathematical models hypothesize that the widespread introduction of varicella immunization programs and consequent reduction in natural boosters could lead to an increased incidence in herpes zoster in adult and elderly individuals [7], [8], [9], [10], [11]. To this regard, analysis of HZ incidence in USA, where universal varicella vaccination was introduced in 1995, showed variable results, since an increasing incidence was reported in some studies, while others did not observe this finding [12], [13], [14], [15]. Moreover, in light of recent proposals to introduce a booster dose in adults 60 years of age or older to prevent zoster in the elderly, the description of case management could provide the basis for cost-benefit analyses comparing treatment and vaccination.
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Materials and methods
We conducted an observational prospective study in Piemonte, a north-western region of Italy, with a population of 3,706,059 individuals 14 years old or older (people over 74 years of age represent 10.7% of this population).
Incidence
During the year of surveillance, 46 cases of herpes zoster were reported in subjects over 14 years of age, accounting for a total incidence of 1.74 cases/1000 population per year (95% CI: 1.28–2.32). The incidence rate by age according to the Poisson distribution is not increased in statistically significant way (Table 1); however, the comparison of the rates of age 15–64 vs. age >64 shows a statistical significant increase (0.85/1000 95% CI: 0.49–1.38 vs. 3.98/1000 95% CI: 2.69–5.68).
56.5% of
Discussion
According to our results, the estimated incidence of herpes zoster in adults in Piemonte is 1.59/1000 person years. This incidence is comparable to that reported in a recent British prospective study [16] involving GPs (1.85/1000), and approaches results of other studies from US (1.2–2.2/1000) [4], [22], UK (2.4–2.6/1000) [23], [24], Iceland (2/1000) [25] and Germany (2.3/1000) [26]. On the other hand, there are various other published European population-based studies, which show higher values
Acknowledgments
The authors would especially like to acknowledge the support of GPs Marilena Di Sario and Patrizia Piano.
This work was supported by a grant LOCALE 2006 (research found ex 60% 2005, University of Turin) and a grant PRIN 2005 (prot. MIUR 2005062795_003).
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2020, Diabetes Research and Clinical PracticeIncidence of herpes zoster and postherpetic neuralgia in Italian adults aged ≥50 years: A prospective study
2019, Preventive Medicine ReportsRisk Factors for Herpes Zoster: A Systematic Review and Meta-analysis
2017, Mayo Clinic ProceedingsCitation Excerpt :Most of the studies were adjusted for confounding factors (age, sex, immunosuppressive conditions, and comorbidities). Twenty-seven studies that reported the incidence of HZ by sex were conducted in North America (United States and Canada), Europe (United Kingdom, Spain, France, Germany, Italy, Netherlands, and Israel), Australia, and Asia (Japan, Taiwan, and China) (Supplemental Table).3,10,11,16-39 Almost all studies consistently reported that women are at increased risk of HZ compared with men (pooled RR, 1.31; 95% CI, 1.27-1.34) (Figure 1).
The burden of hospitalisation for varicella and herpes zoster in England from 2004 to 2013
2016, Journal of InfectionCitation Excerpt :So the incidence of varicella admissions in England was at the higher end of these ranges. The annual incidence of zoster admissions in other western countries before the introduction of nationally funded vaccination programmes against varicella and/or zoster varied from 2.7 to 8.4 per 100,000 when the primary diagnosis was used for case ascertainment26–28,30–33 with the exception of 14.2 hospital cases per 100,000 reported by Bilcke et al.25 When both primary and secondary diagnoses were used, the incidence of zoster hospital cases varied from 5.8 to 14.2.26,28–34 So the incidence of zoster admissions in England was well within the range reported for other countries.
Characteristics of herpes zoster-associated hospitalizations in Madrid (SPAIN) before vaccine availability
2016, Journal of InfectionCitation Excerpt :This rate was also higher than those reported at national level, ranging between 2005 and 2010 from 2.38 to 2.35/100,000 person-years.17 These rates were somewhat lower than those found in other countries, ranging from 3.6 to 9.1/100,000 person-years.9,18–21 Only Portugal reported a lower rate, 1.9/100,000, for the period 2000–2010.22
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Zoster Study Group: Enrico Bianco, Livio Bianco, Elda Brunetti, Marco Ceretto, Roberto Cernigliaro, Enrico Chiades, Nicoletta Civallero, Vincenza Condello, Pier Luigi Coppo, Marilena Di Sario, Gian Maria Ferraris, Piera Fracchia, Daniela Gaido, Piergiorgio Giorcelli, Danilo Grassi, Georgios Kalikatzaros, Paolo Lapi, Sergio Panero, Valentino Patrito, Patrizia Piano, Caterina Rovetto, Pietro Sartoris, Lorenzo Scovazzi and Maria Carmela Viccica.