Increasing Incidence of Herpes Zoster among Veterans

Background. The incidence of herpes zoster in the United States has been estimated to be >= 1 million cases annually, with a higher rate in adults older than 60 years. The morbidity of the disease, including postherpetic neuralgia, imposes significant effects on quality of life. We analyzed reports of herpes zoster in the Veterans Affairs (VA) population because these patients are older and could provide a reflection of disease trends in the aging US population. These data will provide a baseline for future analyses of the incidence of herpes zoster after the introduction of the herpes zoster vaccine in late 2007. Methods. To evaluate the trend in the annual incidence of herpes zoster for fiscal year 2000 (beginning October 1999) through fiscal year 2007 (through September 2007), we derived incidence rates using the Veterans Health Administration Decision Support System reports of herpes zoster by International Classification of Diseases, Ninth Revision codes from 2000 through 2007 and the corresponding denominator data for all veterans in care. These rates were validated by review of medical records of patients with diagnoses of herpes zoster at the Atlanta VA Medical Center. Results. The annual incidence of herpes zoster increased from 3.10 episodes per 1000 veterans in 2000 to 5.22 in 2007 (R-2 = 0.9743; P < .001). This increasing rate was seen in both men and women but only in groups older than 40 years. Conclusion. The increasing incidence of herpes zoster in our veteran population and its effect on the quality of life of the veterans validate the need for improved rates of vaccination in this population.