The primary outcome is the burden of illness due to HZ defined by the area under the worst pain versus time curve measured during the 6 month period following HZ rash onset in subjects who develop of HZ. The burden of illness outcome is sensitive to the incidence, severity, and duration of HZ-associated pain. The secondary outcome is the incidence of PHN, where PHN is defined as HZ-associated pain rated as greater than or equal to 3 (on a 0 to 10 scale) persisting or appearing more than 30 days after the onset of the HZ rash.