A pox on their house

Confusion around chicken pox and shingles could be costly to Victoria consumers.

I WAS HALFWAY THROUGH writing my Focus article about the way prescribing guidelines have been hopelessly infected by pharmaceutical industry funding, when two strong wind gusts changed my tack. The first pushed me toward a sandwich board in front of Shoppers Drug Mart on Douglas Street, urging passers-by to come in and get a shingles vaccine. The second was a June 20 report in the Globe and Mail that pretty much sucked the wind from my sails on the issue of corrupted prescribing guidelines. Some of us have been writing about this problem for decades, so I’m happy to see that the scribes at Canada’s national paper have discovered that maybe drug-company corruption of prescribing is actually a major problem.

Sandwich board in front of Shoppers Drug Mart on Douglas Street

But that sandwich board’s bold message of the link between chicken pox and shingles rang like a symphony of bells at Christ Church Cathedral. I’m attuned to a deep ringing chorus of mistruths, but the sorry gap between the medical science and the marketing in this case was begging for a comeuppance. It’s especially urgent given that this case involves someone coming at you with a hypodermic needle.

For starters, the link between varicella zoster (also known as chicken pox) and herpes zoster (also called shingles) is anything but certain. In 1888, Bokai, a Budapest physician, may have been the first to hypothesize the link, but many others have since suggested the same thing. Today the US Centers for Disease Control and Prevention says point-blank that “shingles is caused by the reactivation of the varicella zoster virus (VZV), the same virus that causes varicella (chickenpox).”

According to current medical thinking on the issue, it is believed that once a person has had chicken pox (which is usually mild and happens in early childhood), the virus is thought to remain dormant in the dorsal root ganglia, which are nerve cells. The virus can sometimes erupt (usually in people older than 65) to cause a painful rash, known as shingles.

If you’ve seen ads for Zostavax, Merck’s vaccine against shingles, you’ve an idea of how nasty the condition can be. Rows of red, painful, itchy welts can wrap around your torso, and even infect your neck, face or eyes. While the disease can be particularly bad, and the desire to avoid the torture suggested by fiery strings of barbed wire wrapping around you understandable, the main question we need to ask is: For most of us who had chicken pox as a child, how likely are we to get shingles?

The quick answer is not very. For starters, the research says shingles is simply not that common. One report, examining 21 studies in Europe, found that for kids and young adults it’s rare—somewhere between one to two cases per thousand people per year. That increases to about four per thousand up to age 50, and seven to eight per thousand for people over 50. About one percent of people over 80 are at risk every year for contracting shingles.

Despite the rarity of the disease, fear-mongering and vaccine shilling abounds. Medical journal articles, the Shopper’s pamphlet, and Merck’s ads all tout the “one-in-three odds of getting shingles in your lifetime!” This is the same category of misleading information that says all women have a “one-in-eight lifetime chance of getting breast cancer,” ignoring the fact that this only applies to women who live to be 85.

You can, however, get shingles at any age, and those with immune-deficient conditions, such as HIV, leukemia or lymphoma, have to be very careful. Many otherwise healthy people who get shingles might have a few weeks of troublesome symptoms as the disease goes away on its own. Only about a quarter of shingles cases will result in complications, such as severe rash and pain.

As for the causal link between having chicken pox when you’re younger and developing shingles when you’re older, the jury is still definitely out. One researcher, Dr Chris Shaw, who studies vaccine safety, told me from his office at UBC that in his mind there “is no strong link between chicken pox and shingles,” even though he acknowledges that the official story says the opposite.

I found one study which said that exposure to chicken pox increases your risk of developing shingles later in life, but also showed that adults who live with children are naturally exposed to a lot of chicken pox. The result? This exposure can be “highly protective” against developing shingles later in life.

This is echoed by Dr Eva Vanamee, an adjunct assistant professor at the Icahn School of Medicine at Mount Sinai in New York, who told me by email: “If you are exposed to chicken pox from time to time then your chances of getting shingles is much lower.” What she says next is compelling, and reminds me of the power of immunity: “Pediatricians used to have the lowest incidence [of shingles] due to their constant exposure. So the virus hides out and can cause shingles but the boosting provides protection, which is now pretty much lost with the vaccine.”

So, what does all this mean? Should we allow our kids to naturally get chicken pox, or try to vaccinate against it?

WHEN MY KIDS WERE IN PRESCHOOL, now more than a decade ago, I remember a notice coming home alerting parents that chicken pox was in the school. How did we react? Like most Fairfield parents, we sent our kids off to the pox-infected school anyway. After all, getting exposed to “the real thing” will make you develop the immunity you need, right? We were told that a person seriously doesn’t want to get chicken pox as an adult, so better to expose the little ones now. The funny thing I remember is that a few of the kids who did get the pox had already been vaccinated.

The manufacturer of the Varivax (chicken pox) vaccine admits this possibility on its label: Protection isn’t guaranteed, nor is the duration of protection really understood. Funnily, it adds that the vaccine’s effects on preventing (or getting) shingles downstream are unknown.

Some experts are decidedly wary of the value of the chicken pox vaccine. According to the Vaccine Information Center in the US, “Mass use of chickenpox vaccine by children in the US has removed natural boosting of immunity in the population, which was protective against shingles, and now adults are experiencing a shingles epidemic.” I’d say the prevalence to date I’ve seen hardly suggests an “epidemic,” but it is clear the number of annual cases of shingles have been rising for at least a decade.

So, even if it may not be true, as Shoppers Drug Mart tells us, that chicken pox puts us “at risk” of developing shingles, should we get the vaccine anyway? Based on my reading of the evidence, the shingles vaccine “works,” but I would add one qualifier: “barely.”

A 2005 trial studying the effectiveness of the shingles vaccine published in the New England Journal of Medicine enrolled more than 38,000 people over 60. Over three years, Zostavax reduced “the occurrence of herpes zoster by 51.3 percent.” Here’s the kicker though: The vaccine is measured in “1000-person years” where the effects are noted among 1000 people for one year. The study found that the vaccine dropped the rates of shingles per 1000 person-years from 11.12 (those on placebo) to 5.42 (those given the vaccine). The difference is only 5.7 people per thousand per year (11.12 minus 5.42 equals 5.7). Since 5.42 is “51 percent” less than 11.12, that’s where you get the “51 percent reduction” number.

Let’s be clear: The shingles vaccine won’t make your risk go from 100 percent down to 50 percent—which is what most people think when they see “a 50 percent reduction.” Actually it helps about five people per thousand per year. With those sorts of numbers, the NNV (Numbers Needed to Vaccinate) is 233—the pharmacy would have to vaccinate 233 customers to avoid one person getting shingles. At $230 per dose (current price at Shoppers Drug Mart, including the $20 injection fee), it would cost more than $50,000 to prevent one case of the shingles. Like those odds? How about the fact that in August 2014, the vaccine’s label was updated, telling us that Zostavax might actually cause shingles. What a strange world this is.

THE GOOD NEWS, for me, is that the BC government won’t pay for it. Why? They won’t say, but Lori Cascaden at the BC Ministry of Health told me by email, “the Ministry continues to consider it alongside other vaccines for British Columbia’s publicly funded immunization schedule.”

I have to say, I have a good feeling about pharmacists. The Douglas Street Shoppers pharmacist I chatted with was a very nice guy, and it was clear to me that he went to pharmacy school to help people. I’m sure many pharmacists will have mixed feelings about the business they’re in, working in tandem with corporations flogging vitamins and other supplements, pharmaceuticals that have little effect, or vaccines that are marketed with scare tactics on sandwich boards. I feel for them, and I’d like to see them more as allies in distributing good information about diseases and vaccines, rather than propaganda produced by manufacturers.

 Alan Cassels is a Victoria writer and health researcher. His most recent of four books is The Cochrane Collaboration: Medicine’s Best Kept Secret.