GRAND RAPIDS, Mich. (WOOD) — Health experts say shingles is now infecting patients at a younger age more frequently.

The theory about the shift is that adults who had chickenpox as children aren’t being exposed to it again later in life, so they’re not getting boost to their immune system and are therefore more susceptible to contracting shingles.

Shingles, characterized by a painful, blistering rash, is an infection of the nerve area caused by the varicella-zoster virus, the same virus causes chickenpox. It lies dormant in the body as it recovers from chickenpox.

“What we’re seeing is younger and younger people are having the shingles outbreak and having the complications from the shingles,” said Mary Heim, a pharmacist at Keystone Pharmacy in Grand Rapids.

So far this year, there have been 10 singles patients at Keystone Pharmacy.

The company that produces the shingles vaccine has received approval from the U.S. Food and Drug Administration to draw the qualifying age back to 50. The Centers for Disease Control and Prevention, however, hasn’t extended its recommendations to those as young as 50.

The problem that younger patients are running into is that insurance often won’t cover the vaccine for people in their age range.

“People who see a younger sibling or relative get it go into get the shingles vaccination and then they get denied coverage by their insurance company,” Heim said.

It’s a $260 vaccine if insurance doesn’t cover it, a hefty cost for many.

Heim says people in their 40s or 50s are starting to contract the illness more often, so though the majority of cases occur in senior citizens. In some cases, the people who get it are even younger, like a 31-year-old man from Rockford with visible shingles on his side.

It’s important to note that if you’ve had chickenpox, you’re more susceptible to contracting shingles because they’re caused by the same virus. Health experts recommend getting the shingles vaccine.