Herpes Zoster Vaccination: Impact on the Incidence and Complications of Herpes Zoster Ophthalmicus.

Abstract

Purpose: The incidence of Herpes zoster (HZ) infection in the US is about 1 million/year, of which about 20% have ocular involvement, Herpes zoster Ophthalmicus (HZO). Zostavax™, HZ vaccine, is currently approved for people > 60 years of age to prevent and/or minimize HZ. However, the impact of vaccination is not well known. The purpose of this study is to evaluate the effect of Zostavax on the incidence and complications of HZO.

Methods: Patients were enrolled from the Cornea Service at Massachusetts Eye and Ear Infirmary. The patients’ previous history of shingles, vaccination and clinical courses were recorded. Outcome measures were the age of incidence of HZ, Zostavax™ vaccination, clinical signs, symptoms and complications of HZO.

Results: 341 patients (114 males, 227 females) were enrolled, mean age being 56.0 ±17.6. 165 patients developed HZ; the mean age at the first episode being 59.0±15.6. The mean age of HZ vaccination was significantly higher at 66.7±12.5 (p=0.008). The current cut off of eligibility for Zostavax™ is 60 years; number of patients >60 was 148. Out of the eligible patients, 112 (75.7%) did not get the vaccine and 47.3% of this group developed shingles, while out of the 36 (24.3%) eligible patients who did get the vaccine, only 4% developed the disease. Relative risk of developing HZ was 3.21 in non-vaccinated group compared to the vaccinated group (p = 0.0008).<br /> <br /> Ocular involvement was seen in 85% of HZ; with complications such as residual corneal opacities, secondary glaucoma and cataracts seen in 70%, 8.7% and 5%, respectively in 3.7 years follow up. Out of the 4 patients who developed HZ after vaccination, mean age of incidence was 67±14.

Conclusions: Zostavax™ can decrease the risk of development of Herpes zoster by 3 times. In current practice, the mean age of vaccination occurs 8 years later compared to the peak incidence of disease. Patients should be encouraged to be vaccinated about ten years earlier to minimize the surge in incidence that occurs in the 5^th decade of life. Based on our data as a large tertiary care ophthalmic institute, it is indicative that zoster vaccine delays the age of onset of the first episode of HZO and may result in fewer long term complications even in patients who develop disease after vaccination. Large population studies based on systemic data are required to further elucidate vaccine efficacy.