Over the past week, several of my middle age and elderly patients have requested prescriptions for a Shingles vaccine (Zostavax). There is a lot of marketing (complete with fiery burning barbed wire around a body) about the vaccine so I think it is important to understand the limitations of the vaccine before proceeding.
First, what are shingles? Shingles is a common painful rash (lifetime incidence of 10-30%) that frequently appears as a strip on one side of the body. It is caused by the same virus that causes chicken pox. Read this Mayo Clinic article for information on Shingles. For about 20% of people, the pain can persist even after the rash subsides. This is known as post herpetic nerualgia and the pain can last for months, severely affecting one’s quality of life.
Zostavax is a vaccine for patients over the age of 60 that decreases the likelihood that an individual acquires shingles and PHN. It’s not a foolproof vaccine though - it’s effectiveness can be summarized is as follows:
Put another way, it appears that 59 people need to be vaccinated to prevent 1 case of shingles over 3.1 years, and 364 people need to be vaccinated to prevent 1 case of post herpetic neuralgia over that same time period.
If this wasn’t confusing enough, there are a couple additional points to consider:
- The efficacy of the vaccine appears to decrease with time. Studies show that it loses its effectiveness 6 years after vaccination.
- The vaccine has not been studied on people who have already had a bout of shingles in the past so it’s unclear as to the effect in such circumstances.
The general conclusion that many physicians draw is that the vaccine does work, but it’s not as effective as we want it to be, it gets less effective as the patient ages, and that we are uncertain about its long term effectiveness.
This level of effectiveness against Shingles and PHN’s must also be balanced against the out-of-pocket cost of the vaccine (~$200) as well as its side-effects.
If you have read this far and you are disappointed by the vaccine’s effectiveness, do not despair. I read just this week that there is a new trial Shingles vaccine that is much more effective (up to 97%!) in older age groups.
Check out this RxFiles article on the shingles vaccine for some nitty gritty statistics. You can also check out this blog post for another take on the issue. Magenta Health MDs do not have any association with the manufacturers of Zostavax. If you have more questions, feel free to talk to your Magenta Health physician or register as a patient.