Debbie Hoffman was hoping to get the second recommended dose of the new more effective shingles vaccine on Monday.

But instead her clinic, Park Nicollet in Shorewood, called and said it didn't have any more doses of the Shingrix vaccine in stock. The clinic told her it might not get any more by the end of the year.

It is all part of a nationwide shortage of a vaccine that came to market earlier this year and has proved to be extremely popular because it nearly doubles the protection against shingles, a painful condition that starts with a rash but can morph into a burning sensation that affects nerves and the skin.

Shingrix is recommended for anyone age 50 and older who had the chickenpox, a virus that lies dormant in the body even after the symptoms of the childhood disease go away. The vaccine, which is recommended by the Centers for Disease Control and Prevention (CDC), is 95 percent effective against shingles among adults ages 50 through 69. At older ages, the protection drops to 91 percent.

But that level of protection requires two doses of the vaccine given within a six-month period.

Hoffman, who got her first dose two months ago, is concerned that her clinic won't be able to provide the final dose. That could set her off on a scramble to get a shot within the next four months.

"I am on a waiting list," said Hoffman. "I don't understand how they can have this big push to have everybody get this Shingrix vaccine and then not have it available."

Like many baby boomers, Hoffman knows of others, including her father, who suffered the pain and discomfort of shingles. One in three people who had chickenpox will get shingles in their lifetime.

"I decided to get it after my dad had the shingles," she said. "He had a lot of side effects and it lasted for a while."

About 54,000 Shingrix shots have been given in Minnesota this year, according to the Minnesota Department of Health. That is three times as many as the 16,500 shots given during the same period last year of Zostavax, the older vaccine that was only about 50 percent effective. However, Zostavax required one dose and it was recommended only for those 60 and older.

Minneapolis-based Allina Health said it was able to get Shingrix when it was first available this year, but since May some orders for its clinics were not getting filled.

"Back in March we were placing orders and receiving them on a regular basis. That was before the tidal wave started," said Lee Mork, director of pharmacy for Allina's clinics.

"I don't anticipate that this will get better in a few months," Mork said.

Allina has received some doses and will prioritize those for patients who had been given the first dose and are waiting for the second.

HealthPartners, which owns Park Nicollet, said it also has been affected by the shortage.

"We are working directly with the manufacturer to receive more shipments of the vaccine, although the vaccine is on back-order through 2018," according to a company statement.

It also said it will be "reaching out to all of our patients who are eligible for Shringrix with next steps."

GlaxoSmithKline, which makes the vaccine, said "unprecedented" demand for Shingrix will cause ordering and shipment delays this year, but it has the capacity to vaccinate more patients in 2018 compared to those who got the older vaccine last year.

"We've informed the CDC that we are focused on a fair and equitable allocation plan across all customer segments, to help ensure patients complete the two-dose series," the company said in a statement.

Glenn Howatt • 612-673-7192