The Kentucky teenager who caught chickenpox after refusing to be vaccinated for religious reasons may not realize there can be lifelong consequences from being infected with a herpes virus.

The attorney for the family of Jerome Kunkel, 18, told NBC News that the Kentucky health department had overreacted with an order for unvaccinated students to stay away from school during a chickenpox outbreak in March.

The Kunkel family says they don't regret the teen catching the virus because he's now immune.

“It’s pretty funny, they make a mountain out of a molehill," Christopher Wiest, the Kunkel family attorney, said. "Jerome got it and was a little bit itchy and went back to school."

Chickenpox is a type of herpes

But like many people who view chickenpox as just a normal part of growing up, they may not realize that recovering from the disease doesn't mean the virus is gone, or that they're immune from a future problem.

In fact, chickenpox — technically known as the varicella zoster virus — is a type of herpes virus that, just like its close relative herpes simplex, becomes a lifelong resident in the body.

And like its other cousin, genital herpes, varicella may be silent for many years, hiding out inside nerve cells and can reactivate later, wreaking havoc in the form of the excruciating skin disorder, shingles.

Chickenpox “is erroneously thought of as a not-too-unpleasant rite of passage of childhood,” said Dr. Nina Shapiro, a professor at the University of California, Los Angeles, School of Medicine, who is the director of pediatric otolaryngology at UCLA, and the author of “Hype: A Doctor's Guide to Medical Myths, Exaggerated Claims, and Bad Advice — How to Tell What's Real and What's Not.”

The image of chickenpox as a benign disease has led to some poorly thought out behaviors, like taking children to chickenpox parties, Shapiro said in an email.

A person has to have had chickenpox in order to develop shingles. If a person has never had chickenpox, they will not develop shingles.

Those kids may pay the price decades later, experts say. That’s because the chickenpox virus hides out, dormant, in nerve cells all over the body, waiting for an opportunity to explode back into action as shingles, the blistering, burning skin rash. And shingles comes with its own risks: People who developed shingles had an almost 60 percent higher risk of heart attack and a 35 percent higher risk of stroke, according to a recent study. About 1 million people develop shingles each year in the United States, according to the Centers for Disease Control and Prevention.

“Anything that weakens a person’s immune system — mental and physical stress, HIV, cancer, severe illness, surgery, medications or chemo or radiation therapies, transplant — increases that person’s risk for developing shingles no matter the age,” said Dr. Tina Tan, a professor of pediatrics at Northwestern University’s Feinberg School of Medicine and a pediatric infectious disease specialist at the Robert H. Lurie Children’s Hospital.

That said, “shingles occurs more commonly as a person ages, with a significant increase in occurrence in persons 50 years of age and older,” Tan said in an email. “Anyone who has been infected with varicella-zoster virus is at risk for developing shingles.”

Older people are more susceptible because our immune systems decline as we age, Tan said.

Shingles shows up on one side of the body or face as a rash that consists of painful blisters that typically scab over in seven to 10 days, according to the CDC. One to five days prior to the eruption of the rash, people often experience pain, itching or tingling. The condition can also come with fever, headache, chills and an upset stomach. The CDC estimates that one in three people will develop shingles at some point in their lives.

Even after a person gets over a bout of shingles, the pain may not completely subside. Some continue to experience “post herpetic pain” where the rash erupted.

Shingles can get in the eyes

And in a frightening complication, shingles can affect the eyes and lead to loss of vision.

The number of Americans diagnosed with these eye complications tripled between 2004 and 2016, according to a large study researchers from the University of Michigan’s Kellogg Eye Center presented last week at the 2019 Association for Research in Vision and Ophthalmology annual meeting in Vancouver.

In fact, the eyes are involved in about 15 percent of people who develop shingles, said Dr. Ivan Schwab, a clinical spokesperson for the American Academy of Ophthalmology and a professor of ophthalmology at the University of California, Davis.

What happens, Schwab explained, is that shingles follows a single branch of nerves. If it affects the branch that goes to the face, the eyes can be involved. Along with the pain, it can damage vision or cause blindness in a small percentage of patients.

“Others may have less damage, but enough to affect their lives," Schwab said. "A surgeon, for example, may no longer be able to operate.”

How to avoid shingles

The best protection against shingles is to never get chickenpox.

“A person has to have had chickenpox in order to develop shingles,” Tan said. “If a person has never had chickenpox, they will not develop shingles.”

For people over age 50 who had chickenpox in the past, doctors say, the best defense against developing shingles is the Shingrix vaccine.