This month’s Harvard Health Letter has an article about getting shingles a second time or even a third time. (Click here to read the full article.) The bottom line is that recurrence is a) certainly possible and b) if some recent research is correct, much more common than previously thought and about as likely as getting shingles in the first place if you’re age 60 or older.
I talked to Barbara P. Yawn, director of research at the Olmsted Medical Center in Rochester, Minn., for the March article and mentioned results that she and her colleagues first presented at a conference several years ago.
Yawn reported a more complete version of those results in last month’s issue of the Mayo Clinic Proceedings (a favorite journal of mine). Full text of the study isn’t available unless you have a subscription to the journal, but here is a link to a summary (in medical publishing, such summaries are called abstracts).
Melinda Beck, a health columnist for the Wall Street Journal, had a column about shingles last week and this how she neatly summed up Yawn’s research:
For the new study on shingles recurrence, researchers at the Olmsted Medical Center in Rochester, Minn., examined medical records of nearly 1,700 patients who had a documented case of shingles between 1996 and 2001. They found that more than 5% of them were treated for a second episode within an average of eight years—about the same rate as would typically experience a first case.
And here is a link to the Journal Watch item of the study and a short comment by the Journal Watch editor. Journal Watch is a monthly newsletter published by the Massachusetts Medical Society that summarizes and comments on recently published research.
In the Mayo paper, Yawn and her colleagues report that 95 of the 1,669 people with an “index” case of shingles got shingles again over the course of a follow-up period that averaged 7.3 years, which works out to about 5.6% of the shingles sufferers. Six people had two recurrences and two had three! The timing of recurrence varied from 96 days to 10 years after the initial episode. In 45% of those who got shingles again, the site of the recurrence was in a different region of the body than the site of the first case. They also noted that the single biggest risk factor for having a second case of shingles was having pain that lasted 30 days or longer during the first case.
Other studies have shown the recurrence rate to be much lower. Yawn and her colleagues said a longer follow-up period is one explanation for their results:
Studies that include 1 to 2 years of follow-up may underestimate the average yearly recurrence rates over a lifetime. A reliable estimate of HZ [HZ stands for herpes zoster, the more formal medical term for shingles] requires several years of follow-up. In our study, few recurrences occurred in the first 12 to 18 months after the index case, except in those who were immunocompromised. Our two-year recurrence rate (2.0%) is similar to that reported by Donahue et al but is poorly predictive of the eight-year recurrence rate.
They also said their study probably did a better job than most at capturing all the shingles cases:
Unlike other studies, our cohort came from a community-based population with a well-established infrastructure to report administrative diagnoses and allow access to medical records for in-depth review. The ability to obtain follow-up information across all health care facilities within the county is likely to have ensured a high degree of completeness of recurrence identification.
There is a vaccine against shingles, called Zostavax that is made by Merck (Merck funded Yawn’s research, along with the National Institute of Arthritis and Musculoskeletal and Skin Diseases and the National Institute on Aging). Zostavax isn’t guaranteed protection against shingles. But in the large clinical trial that led to its approval by the FDA, the vaccine did cut the risk of getting shingles in half and the risk of pain that lingers after the signature shingles rash is gone, called postherpetic neuralgia, by even more.
So should people who have had shingles get the vaccine to lower their chances of getting it again?
That’s what the March 2011 Health Letter article is about and you’ll find more details there (click here for full-text access to the article). Factors to consider are cost (Medicare coverage is funky), side effects (it seems from a study published last year that you don’t need to worry about major side effects), and, yes, the chances that you’ll get shingles a second or even third time (they’re real enough, if Yawn’s research is to be believed, and perhaps especially so if your first bout of shingles included a long period of lingering pain).
But, quickly, a key point: Zostavax may very well protect against shingles recurrence, but that’s an assumption at this point. No studies have been done that show that to be the case. When I asked Merck officials about this, I was told in an email that no such study is planned.