A new vaccine is coming out early next year that's expected to save most people over 50 from getting a painful shingles rash.

The vaccine, Shingrix, prevented infections in about 90 percent of the people who had the shot, including those in their 70s and 80s, according to the manufacturer, GlaxoSmithKline.

"It's fantastic prevention by any standard," said Dr. Kathleen Dooling, a medical epidemiologist at the federal Centers for Disease Control and Prevention's Division of Viral Diseases. "This is rarely achieved in people 70 and over."

The only downside? The shots can be painful.

There's only one other shingles vaccine on the market, Zostavax, which was approved in 2006. It's only 50 percent effective.

Shingles is linked to the same herpes virus that causes chickenpox. The Centers for Disease Control estimates that more than 99 percent of adults have it.

The virus never fully leaves the body. It stays dormant, remaining in nerves close to the spinal column.

"For reasons we don't fully understand, it can awaken and reactivate," Dooling said.

A shingles outbreak causes itchy, painful bumps usually on one side of the body, often the face or torso. They typically last three to five weeks.

Every year 1 million people get shingles in the United States, according to the Centers for Disease Control. One in three people are expected to have an outbreak in their lifetime.

People 50 and over are most likely to get shingles. Younger adults can have an outbreak but older people are more at risk because the immune system weakens with age.

The disease can cause severe symptoms, including vision loss and inflammation of the brain. Patients can also develop a type of chronic nerve pain called post-herpetic neuralgia, which can last for months or years.

"While shingles is not deadly, it can be very debilitating," said Dr. Emily Morgan, an internist and gerontologist at Oregon Health & Science University. "It's worth preventing if we can."

Get the shot

The new vaccine, Shingrix, is being shipped to some providers but it is not likely to be widely available across the country, including in Oregon, until the end of March.

Anyone interested in getting a shot should talk to their provider or pharmacy. They should also check with their insurance company or check with Medicare. It could take a little time for insurance coverage to build, said Sean Clements, a spokesman for the manufacturer GlaxoSmithKline.

Besides preventing most cases of shingles, the new drug also cut the number of cases of chronic nerve pain among the few who had an outbreak by nearly 90 percent.

A Centers for Disease Control advisory committee that reviewed the company's clinical trial data and other information recommended that Shingrix be taken by adults 50 and over, including those who have already had Zostravax.

That recommendation is working its way through the CDC bureaucracy. It's expected to be become official early next year, Dooling said.

The drug could be a blockbuster for GlaxoSmithKline. AARP estimates that by 2020 about 120 million people will be 50 and older in the United States.

The drug, which is given in two doses between two and six months apart, will retail for about $280, said Sean Clements, a company spokesman.

The Food and Drug Administration approved Shingrix for sale last October after reviewing the company's clinical and other information. GlaxoSmithKline held a series of trials involving 38,000 people. About 17,000 actually got the vaccine.

The company has shipped some vaccine to providers but Clements doesn't expect it to be fully available across the country until late March.

By then, Clements said, the CDC recommendation should be published. That, in turn, will prompt consideration by insurance companies. Medicare, used as a guide by many insurers, generally covers recommended vaccines though some have to be administered by a pharmacy – not a doctor's office.

People who had the vaccine four years ago are continuing to be followed, Clements said. Tests show that the vaccine doesn't lose its effectiveness in that time.

But the shots can produce a redness and soreness at the injection site. Some people experienced other symptoms, including headache, fatigue and muscle aches.

About 17 percent of those who got the vaccine experienced enough side effects that they couldn't do their regular activities for a few days, Dooling said.

"These reactions didn't seem to have any long-lasting effects on health," Dooling said. "They are something that people should be aware of before getting the vaccine."

The vaccine doesn't contain live virus. Rather it includes a protein on the outside of the virus that teaches the immune system to fight it. It also contains an additive that acts as booster to the vaccine.

That additive is one the reason the shot can cause discomfort. It elicits an immune response almost immediately, Clements said.

-- Lynne Terry