Zdravniški Vestnik (Sep 2006)
Herpes zoster – available epidemiological data in Slovenia
Abstract
Background: Herpes zoster results from reactivation of latent varicella zoster virus (VZV) in dorsal nerve ganglia. Herpes zoster is characterized by a painful dermatomal vesicular rash. Reactivation results from impaired cell-mediated immunity. The determinants of reactivation in individuals with no underlying immunosuppression are poorly understood. The introduction of vaccination against varicella is expected to lower the incidence rate of chicken pox. The influence of vaccination on herpes zoster morbidity is not clear and demands enhanced surveillance. Before the introduction of vaccination, the available epidemiological data should be analyzed for the availability, value and shortcomings.Methods: The data from two electronic data-sets of Institute of Public Health of the Republic Slovenia were analysed: notified cases and number of consultations on primary level for herpes zoster – »ZUBSTAT« (data set of all first visits in primary care, Institute of Public Health of the Republic Slovenia). The data were stratified by age and sex. The hospitalization data were extracted from Eletronic data set for diseases which require hospitalization (entitled BOLOB, IPH). For notified and hospitalized cases also the month when shigles appeared was available.Results: The number of notified cases increased steadily from year 1995 when mandatory reporting has been implemented. In year 2005 the incidence rate rose to 74/100,000. Approximately a quarter of cases (23.4 %) was 70 years of age or older. According to the second data-set, which encompasses first visits in primary care, 5891 to 6527 patients were coded as herpes zoster. The incidence rate increases with age, being highest after age of 65 years (675 to 760/100,000). Women have higher incidence rate of herpes zoster in almost all age groups. The distribution of notified cases suggests seasonal peak in summer. The highest number of admissions was in September and October.Conclusions: The number of mandatory notifications is increasing, but the notification system still records less then a quarter of cases compared to ZUBSTAT. The disadvantages of ZUBSTAT data set are fixed age groups and lack of possibility to analyse the data for shorter time periods e.g. by month/week, which is important for epidemiological surveillance. To obtain better data, the prospective epidemiological study is needed.
