Seasonality of herpes zoster and herpes zoster ophthalmicus.

BACKGROUND: Herpes zoster (HZ) and herpes zoster ophthalmicus (HZO) are common and debilitating diseases. There is no consensus in the literature whether HZ and HZO exhibit seasonal patterns. OBJECTIVES: To determine whether HZ and HZO are seasonal. STUDY DESIGN: All patients in the OptumLabs® Data Warehouse (OLDW), a longitudinal, insurance claims database with de-identified lives between January 1, 2006 and December 31, 2017 with 365 days or more of continuous enrollment were considered in the study. The database was queried for patients reporting a new ICD-9/ICD-10 code for HZ or HZO and monthly counts of each administrative code were modeled using Morelet wavelets and analyzed for annual periodicity using Fisher's g test. RESULTS: There were a total of 513,911 new cases of HZ during this time period; 40,166 cases (7.8 %) were reported as HZO. Administrative coding for new cases of HZ exhibited annual periodicity (P < .001) with a peak in the summer. No periodicity was evident for HZO. CONCLUSIONS: These results contribute to a growing body of evidence suggesting that HZ may be seasonal and help characterize the epidemiology of this common, painful disease.