Herpes Zoster Ophthalmicus and Vision Loss

Shingles is generally considered to be an illness of the elderly, who are at greatest risk. Half of all cases in the United States occur in people over the age of 60. But shingles is on the rise among younger individuals as well.

Of the estimated 1 million cases reported each year in the United States, HZO is diagnosed up to 20% of the time. The results of 1 study reported that the incidence of HZO increased by 3.6% per year between 1994 and 2018.2

HZO occurs when the dormant varicella zoster virus reactivates along the ophthalmic branch of the trigeminal nerve.Early symptoms include fever, a rash on the forehead, eyelid swelling, eye pain and redness, and sensitivity to light. In addition to vision loss, other complications include increased pressure within the eye and chronic pain.

The Australian study focused on determining the rate of moderate and severe vision loss following HZO, and identifying causes and factors associated with permanent vision loss due to HZO.¹

Investigators reviewed the records of 869 patients with acute HZO who were seen at 1 center between 2006 and 2016. The median follow-up time was 6.3 years. Ocular involvement occurred in almost 85% of cases. Moderate vision loss, defined as greater than or equal to 20/50, and severe vision loss (≤20/200) secondary to HZO were both measured. Moderate loss occurred in 83 eyes (9.6%), whereas severe vision loss occurred in 31 eyes (3.6%).¹

Conjunctivitis, keratitis, and uveitis were the most common sites of ocular involvement. The causes of vision loss included corneal scarring (94%), corneal perforation (4.8%), and secondary glaucoma (1.2%).¹

“Among individuals with HZO, approximately 1 in 10 individuals may develop moderate or severe vision loss, primarily due to corneal scarring,” the investigators concluded.¹ “Older age, immunosuppression, and uveitis are associated with severe permanent loss of vision secondary to HZO.”

Vaccination is the best available protection against herpes zoster and HZO. Shingrix, the only shingles vaccine available in the United States, is approved for use in individuals age 50 and older. It can be administered to patients who were previously vaccinated with Zostavax, which has been withdrawn from the US market, or to those who have already had a case of shingles.

The American Academy of Ophthalmology (AAO) issued a policy statement in 2017 recommending herpes zoster vaccination, noting evidence that HZO increasingly affects younger adults with a mean age of onset of 52 years. The organization added that postherpetic neuralgia, a debilitating complication of shingles, is more likely in patients with ophthalmic involvement.³

“Vaccination starting at 50 years of age will reduce the burden of this disease, including chronic eye disease,” the statement concluded.³

AAO encourages ophthalmologists to proactively promote shingles vaccination to their patients by partnering with local pharmacies that offer on-site clinics for vaccine administration.³

References

1. Niederer RL, Meyer JJ, Liu K, Danesh-Meyer HV. Herpes zoster ophthalmicus clinical presentation and risk factors for loss of vision. American Journal of Ophthalmology. February 8, 2021. Doi: https://doi.org/10.1016/j.ajo.2021.02.002

2. Kong CL, Thompson RR, Porco TC, Kim E, Acharya NR. Incidence rate of herpes zoster ophthalmicus: A retrospective cohort study from 1994 through 2018. October 9, 2019. Doi: https://doi.org/10.1016/j.ophtha.2019.10.001

3. Recommendations for herpes zoster vaccine for patients 50 years of age and older. Policy statement. American Academy of Ophthalmology; August 17, 2018. Accessed April 29, 2021. https://www.aaojournal.org/action/showPdf?pii=S0161-6420%2818%2931727-5