DRUG BUST by Alan Cassels
The people's briefing note on prescription drugs

Judy M., who lives in Victoria, sent me an email asking what I knew about a vaccine to prevent a truly nasty condition called shingles. Being the third such request I’d received in as many weeks, I figured it was time to take a closer look at the shingles vaccine. Shingles, also known as herpes zoster, can cause a serious and very painful rash.

Judy’s friend Jane was urging her to get vaccinated for shingles. Jane’s husband Stan had a case of shingles that Stan described as “worse than anything he has ever known, including spinal surgery.” Sometimes, open sores accompany the rash and the pain is so severe people have trouble walking and sleeping. In rare cases, the complications of shingles can last for months and sometimes years.

That fact surely caught Judy’s attention. In fact, she admitted she had a profound fear of the disease having seen her aunt go through postherpetic neuralgia where the pain continues to last even after the rash and blisters have disappeared. In her opinion, any level of pain seems bearable if you know it will eventually end, but the thought of living with such pain for life made a compelling argument for getting vaccinated.

So what could I say about the vaccine called Zostavax being promoted to prevent shingles?

I always like to start my research by looking at the pointy end of things: the marketing. If there is one principle in play, it’s that the marketing diverges from the science. And since the advertising is what patients and physicians will likely see first, that’s a good place to start. The ads for Zostavax, made by drug giant Merck, lay out the hook in bold letters: “Have you had your shingles vaccine yet?”

In typical marketing style, that innocent question is driven home by the fear factor, reminding us that this is something we all need to be worried about. In smaller print, the ad says, “In Canada, it is estimated that nearly 1 in 3 people will develop shingles in their lifetime.”

Ok, if true, this establishes that shingles doesn’t seem to be such a rare condition. Most of us who have had chicken pox as children are susceptible and it usually strikes people over 60, though no one is really sure how or why this happens.

Many of us know someone, maybe our mother, friend or neighbour, who has a horror story to tell about the unbearable pain shingles can deliver. I didn’t have to go far to hear some anecdotes. I asked my mother about it and learned that she had had shingles a few years ago that lasted several weeks, which included three visits to the hospital and incredible pain across her stomach. Treatment for shingles usually involves antivirals (drugs such as acyclovir), which, if given early enough, can help shorten the length and intensity of the rash.

The vaccine marketer captures the disease’s potential for serious pain with graphic ads featuring a lot of flames and thorns with a clear and unspoken question: “Do you want your life to be a living hell?”

Now that we’ve established the nastiness of the disease, the first question has to address the science: “Does the Zostavax vaccine work?”

If a vaccine is about protecting you from a disease, you need to know your likelihood of getting the disease in the first place. One study from the British Medical Journal says that for people over 50, approximately two to three people out of a thousand per year get shingles; that increases to about eight per thousand for those 70 and over. The average doctor with 1,500 patients in his care would see about three to five cases per year.

A 2005 study in the New England Journal of Medicine enrolled over 38,000 people over 60 and reported that, over three years, the vaccine Zostavax “reduces the occurrence of herpes zoster by 51.3%.”

Wow. So if you know 100 people who got vaccinated, the vaccine would prevent half of them from getting shingles, right?

Wrong. Remember, if the average doctor sees five cases a year in his practice and he manages to reduce that load by 50%, he’d only see maybe 2.5 cases per year. But how many thousands would he have to vaccinate to prevent those other 2.5 cases? A lot.

This study of the vaccine, which was a gold standard, randomized, double-blind, placebo-controlled trial, measured the incidence, severity and duration of the pain caused by shingles. Let’s focus on just one of those: incidence. Basically, how many people were prevented from getting shingles?

The study noted there were 315 shingles cases among those vaccinated and 642 among placebo recipients, concluding that it reduced the rate of shingles by 51.3 percent. Another way this is expressed is in “1,000-person years” where the effects are examined in 1,000 people for one year. The study found that the vaccine dropped the rates of shingles per 1,000 person-years from 11.12 (those on placebo) to 5.42 (those given the vaccine).

What this means is the vaccine ‘helps’ about 5.7 people per thousand per year (11.12 minus 5.42= 5.7). Where did the “51.3 % reduction” come from? Well, when you drop the rate from 11.12 to 5.42, that’s about half the rate, or a 51.3% reduction.

To summarize, here are two ways of presenting the same data: 1) “The vaccine helps five people per thousand vaccinated. Or 2) “The vaccine helps 50% of the people vaccinated.”

Hmmm. You can imagine which one gets the most traction with the marketers.

So let’s talk cost. If you have to vaccinate 1,000 people per year at $150 a shot, it would cost $150,000. That’s a fair bit of money to save five people from getting shingles. In other words, the cost of avoiding shingles is about $30,000 per person per year.

Does that sound like a bargain? Depends on whom you ask. If you asked Judy’s friend Jane, she’d probably say that not seeing her husband in such pain is “priceless.” If you ask governments to pay for the vaccine, seems they think it’s too high a price to pay and it isn’t covered in BC. It’s not that the vaccine doesn’t work; it’s that it hardly works.

And that’s before you wander into the other side of the equation: the vaccine’s potential for adverse effects. By August 2011, in the US, the federal Vaccine Adverse Event Reporting System (VAERS) had received 442 serious vaccine adverse reports following Zostavax vaccination, including 36 reported deaths. While these are ‘associations’ and not causations, it still makes one pause before hitting the “jab” button. The kinds of serious shingles vaccine reactions included things like joint and muscle pain, fever, abnormally swollen glands and so on.

Some might ask, “Is it possible the vaccine can actually cause shingles?” A good question to which there is no definitive answer, but rashes akin to chicken pox are mentioned on the vaccine’s label as one of the potential adverse effects.

At the end of the day, facts can be twisted in any way to make a point, especially when the ‘point’ comes at the end of a syringe.

But back to Jane who was caring for her husband and his very nasty bout of shingles. Seeing Stan in such pain was enough for her. She begged Judy and her other friends to get vaccinated. She went and paid the $150 to get herself vaccinated.

And a few weeks later? You guessed it; she too came down with a new diagnosis.

That’s right, shingles.

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Alan Cassels is a pharmaceutical policy researcher at the University of Victoria and the author of Seeking Sickness: Medical Screening and the Misguided Hunt for Disease (Greystone, 2012). You can follow his interests on Twitter at AKECassels or read more of what he's writing about at www.alancassels.com