Doctors encourage inoculation against painful shingles, laud new vaccine
This image provided by GlaxoSmithKline shows the company's Shingrix vaccine. (GlaxoSmithKline via AP)
Like many Canadians, Anne Van Burek had chickenpox as a child. But she never expected the virus that causes the itchy rash to come back to haunt her decades later.
In February, Van Burek developed shingles, a highly painful skin rash caused by the varicella-zoster virus that can become reactivated as people age and the strength of their immune systems begin to wane.
The rash started with a couple of blisters on her right hand, then spread up her arm to her shoulder.
"The pain was indescribable," Van Burek said Tuesday. "I couldn't unscrew the toothpaste tube.
"I was completely disabled. February, March were a black hole, April a black hole. I started to be able to get dressed and go out for short walks in May," said the French teacher at a private Toronto girls' school, who wasn't able to return to class for the rest of the school year.
Van Burek, who's in her 60s, had developed postherpetic neuralgia — an often excruciating complication of shingles that affects 10 to 30 per cent of those who get shingles, with incidence increasing with age.
But the onslaught of shingles can be prevented with vaccination, doctors say.
A shingles vaccine called Zostavax currently available in Canada decreases cases of shingles by about 50 per cent in those previously infected with chickenpox, and reduces the risk of postherpetic neuralgia by about 67 per cent.
"But the thing about that vaccine, though, is the older you are, the less likely you are to respond to it," said Dr. Mark Loeb, an infectious diseases specialist at McMaster University in Hamilton, Ont. "So people over the age of 80, only about a quarter of them were protected from postherpetic neuralgia."
However, a new vaccine called Shingrix, approved by Health Canada last month and available in January, has been shown in clinical trials to be more than 90 per cent effective at preventing the nerve pain of shingles in people over age 50, when compared with a placebo.
"The new vaccine is something we didn't think was possible," concedes Dr. Allison McGeer, director of infection control at Mount Sinai Hospital in Toronto, referring to how the product was made and its ability to stimulate the immune system.
Unlike its forerunner manufactured by Merck, Shingrix by GlaxoSmithKline is not made with live attenuated zoster virus, but was created from a protein taken from an inactivated form of the virus, which triggers an immune response in the body, boosted by what's called an adjuvant.
"This vaccine appears to work more than 90 per cent of the time, which is really amazing," said McGeer.
Dr. Susie Barnes, vice-president and country medical director at GSK Canada, said the new vaccine is indicated for adults aged 50 and older and requires two doses given by injection in the arm, two to six months apart.
As with most inoculations, there are potential side-effects, she acknowledged. "The most common ones we see are the local reactions, so pain, redness and swelling at the site of the injection.
"And also, people can experience things like headache, muscle ache, fever," Barnes said, describing these symptoms as typically mild and lasting about three days.
"At the same time, if there's something that lasts longer or is more severe than expected, we always make sure that people speak to their health-care professional."
Barnes wasn't able to say how much Shingrix will cost Canadians, but noted that it would be no more than 30 per cent higher than the cost of Zostavax, which carries a price tag between $170 and $200 for two doses.
That cost would have to be paid out of pocket by consumers or by private drug insurers; Ontario is the only jurisdiction in Canada to cover the cost of Zostavax for residents 65 to 70, she said, and it's unclear if the province or others will decide to pick up the bill for Shingrix once it comes on the market next year.
Still, inoculation against shingles is recommended for Canadians aged 60 and older by the National Advisory Committee on Immunization (NACI), although that advice applies only to the currently available product. Those 50 to 59 may also consider getting the shot, NACI says.
McGeer said shingles can be "enormously debilitating," adding that it makes sense for people to get vaccinated, given that about 30 per cent of people who have had chickenpox will develop shingles at some point in their lifetime.
"So it's definitely a disease worth preventing," she said.
Loeb of McMaster said there are about 130,000 cases of shingles each year in Canada, leading to more than 250,000 doctors visits, with about 2,000 requiring hospitalization.
About 17,000 of those afflicted by shingles go on to develop postherpetic neuralgia, which Loeb said can last weeks to months — and in some cases, years.
In the U.S., the Centers for Disease Control and Prevention recently recommended Shingrix as the preferred vaccine for preventing shingles in adults age 50 and up, based on a close vote by the Advisory Committee on Immunization Practices.
"This is a high-efficacy vaccine," said Loeb, adding that the research evidence supports its use.
"It seems like it's a bit of a no-brainer."