Ask the Pharmacist

Q) I still haven’t decided whether I should get the new shingles vaccine. What are your thoughts on it?

A) The newer shingles vaccine, Shingrix, was approved for sale in Canada back in October of 2017. It has received widespread acclaim from various health authorities for its persistent and remarkable effectiveness at preventing both an outbreak of shingles as well as decreasing the likelihood of post-herpetic neuralgia, the most feared and debilitating long–term complication that might occur post infection.

Shingrix has essentially knocked its only competition, Zostavax, out of the market due to its numerous advantages over its predecessor.

These include first and foremost that Shingrix works better, regardless of the age of the recipient than Zostavax does. Shingrix is reported to be 91% effective versus 53% for Zostavax. Now, what exactly does this 91% mean in terms of staying healthy versus becoming sick.

Well, in one study, a large number of people with an average age of 62 were injected with either Shingrix or a placebo and their health status was tracked for the following 3 years. During this period, six people from the Shingrix side of the study came down with shingles. And on the placebo side? Well the number of cases was 210 (note in this study Shingrix was found to be about 97% effective but it gives you some sense of its potency).

The other remarkable trait about Shingrix’ effectiveness is that it holds up surprisingly well even in our oldest citizens. One of the challenges we face in healthcare is that those who need vaccines the most are our people aged 70 and older as they are both more likely to become infected and to have a more severe case of just about any illness. Unfortunately, this demographic tends to get the least benefit from vaccines (note that I did not say no benefit) since by this age their immune systems no longer respond as heartily to the boost vaccines are designed to provide.

With Shingrix, shingles prevention rates remained at approximately 90% even for those in their 70’s and 80’s, which are numbers that other vaccines (hepatitis, flu…) can’t even come close to comparing to. As well, Shingrix can be used in those with impaired immune systems (such as those undergoing chemotherapy or on corticosteroids) because it is a non-live vaccine whereas Zostavax (a live vaccine) cannot be administered to these same individuals due to the risk that it cause an infection with their compromised immune state.

Shingrixis is also judged to be a better value despite its higher price tag (the 2 shots will cost you over $300) when you factor in the likelihood of missing work and the costs of treatment should you come down with a case of shingles. Shingrix also seems to work for a much longer period of time than Zostavax does.  Experts still are not sure when or even if a booster dose will be required in the future but based on early returns they expect the immune system boosting effects to last at least a decade.

For Zostavax, the immune response was already rapidly decreasing by year four. On the negative side, Shingrix does require 2 shots (to be administered between 2 and 6 months apart) versus one dose for Zostavax and the risk for having an adverse reaction is slightly higher with Shingrix.

Side effects with Shingrix tend to be largely related to getting a needle itself with pain at the injection site being by far the most common with 78% reporting that the injection hurt to some extent. Other complaints include redness and swelling at the site and some people have a more systemic reaction and complain of side effects such as muscle pain, fatigue, a headache or fever which happen in 20-40% of people and generally last from a few hours to two or three days.

Very few people found they needed to miss work or other activities because of these side effects and serious life altering adverse events have not been directly attributed to Shingrix although due its relative newness on the market, researchers are continuing to watch it closely. In general, complaints were more common after the second dose than the first.

As mentioned earlier, Shingrix has also proven to be of benefit even when it doesn’t prevent a person from getting an outbreak of shingles. This is because it reduces the risk of post herpetic neuralgia by 67%. Post herpetic neuralgia (PHN) occurs when the pain doesn’t go away after the rash and the blisters of the initial outbreak disappear. The pain can be severe and may continue for more than a year although most cases disappear after 1 or 2 months. Approximately 1 in 5 people with shingles will suffer from PHN without vaccine protection and will often need to go on prescription type pain killers in order to cope.

There is one more reason to strongly consider receiving a shingles vaccine and this is based on a study only recently completed. In it, people who had previously received a shingles vaccine (in this case it was Zostavax but experts expect the same or better results from Shingrix) had a lower chance of suffering a stroke. There was a 20% reduction in stroke risk in people under the age of 80 and a 10% decrease in those older.

The hypothesized reason behind this unexpected benefit is not really due to the vaccine itself but is rather due to the decrease in the number of people who suffer an outbreak of shingles as a result of being vaccinated. Shingles increases the amount of inflammation within the body. One of the many factors that seem to affect one’s risk of suffering from a stroke is inflammation, with those that have higher amounts seemingly more at risk. The study showed that both types of stroke (bleeding or blockage) were significantly reduced allowing experts to state that if these effects are proven to be true, it is yet one more powerful argument in favour of shingles vaccination.

It is estimated that half of us will develop shingles by the age of 85 and the current recommendations from Health Canada is that any individual 50 years of age or older should strongly consider receiving the vaccine. For more information about this or any other health related concerns, contact your pharmacist.