The shingles vaccine prevents incident herpes zoster and post-herpetic neuralgia in older individuals, even those who are immunocompromised, researchers found.
In a study of Medicare beneficiaries, the rate of incident zoster was significantly lower among those who received the vaccine (5.4 versus 10.0 cases per 1,000 person-years), according to Sinéad Langan, MBBCh, PhD, of the London School of Hygiene & Tropical Medicine, and colleagues.
That works out to a vaccine effectiveness of 48% (95% CI 39% to 56%); effectiveness was lower but still significant among those who were immunocompromised (37%, 95% CI 6% to 58%), the researchers reported online in PLOS Medicine.
And for post-herpetic neuralgia occurring 90 days or more after zoster, vaccine effectiveness was 59% (95% CI 21% to 79%).
Not many people in the study received the benefits of vaccination, however, since only 3.9% received the vaccine.
"Despite strong evidence supporting its effectiveness, clinical use remains disappointingly low with particularly low vaccination rates in particular patient groups," Langan and colleagues wrote.
"As post-herpetic neuralgia is the major complication of herpes zoster and is associated with highly significant morbidity and adverse impacts on quality of life," they continued, "substantial efforts are needed to increase vaccine use in routine care of elderly individuals."
Previously, the shingles vaccine was proven effective against incident herpes zoster and post-herpetic neuralgia in clinical trials -- including the Shingles Prevention Study -- and in selected populations -- including members of a large managed health plan. But effectiveness had not been explored in a real-world, unselected population of older individuals.
The current study included 766,330 Medicare beneficiaries who either did or did not receive the shingles vaccine during the 3-year period from 2007 through 2009.
According to administrative data, few individuals were vaccinated, with uptake especially low for those 80 and older (1.5%), those with a low income (0.6%), and black individuals (0.3%).
During the study period, 1.7% of the beneficiaries developed incident zoster, with a significantly lower rate among those who were vaccinated after adjustment for age, sex, race, income, immunosuppression, and zoster-related comorbidities. The vaccine was effective even in those who had the immunosuppressing conditions of HIV, leukemia, and lymphoma.
The CDC recommends that all individuals 60 and older receive the shingles vaccine -- which is approved for use in those 50 and older -- although immunosuppression is a contraindication to vaccination. "Given that [immunosupressed] individuals are at greatest risk of both herpes zoster and complications, [the current findings] may have important implications for policy," the researchers wrote.