Shingles can be an agonizing, chronic condition for people who once contracted chickenpox, as the virus resurfaces as a persistent rash. And when it affects the eyes, shingles (formally known as herpes zoster ophthalmicus) can scar corneas and cause loss of sight.

According to new research from the University of Michigan Kellogg Eye Center, cases of eye shingles tripled among a group of 21 million Americans between 2004 and 2016.

The Mayo Clinic recommends anyone over 50 gets a new shingles vaccine scalled Shingrix

Most at risk: Women and adults over age 75.

According to the Mayo Clinic, shingles is caused by the varicella-zoster virus behind chickenpox. Years after the pox subsides, HZO in nerve tissue can be activated by stress or a weakened immune system to re-emerge as shingles.

The Mayo Clinic recommends anyone over 50 gets a new shingles vaccine scalled Shingrix to help prevent the disease and allay symptoms.

“Older patients were at far greater risk for HZO, highlighting just how important it is for older adults to get the shingles vaccination,” study author Nakul Shekhawat, a comprehensive ophthalmologist at the University of Michigan Department of Ophthalmology and Visual Sciences, told Science Daily.

According to the Kellogg Eye Center research, cases of HZO rose substantially across the United States between 2004 and 2016: from 9.4 cases per 100,000 people in 2004 to 30.1 cases per 100,000 by 2016.

In another study published last month in the British Journal of Ophthalmology, Kellogg researchers described one route to recovery from eye shingles: corneal transplants that replace the affected tissue entirely.

For the rest of us, a shot of Shingrix is 90% effective in staving off this painful condition, the Kellogg team said.

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