In a study involving 38,000 people 60 and older, the shingles vaccine reduced the incidence of shingles by 51 percent and the incidence of post-herpetic neuralgia, or after-shingles pain, by 67 percent, according to the Centers for Disease Control and Prevention. The vaccine works best in people under 70.
The efficacy of the shingles vaccine appears to diminish over time, and it may not protect against shingles after five years, states the CDC. However, the agency does not recommend a booster.
Shingles is an illness that results from the reactivation of the virus that causes chicken pox, notes the CDC. Known as varicella zoster, the virus remains dormant in the body after the initial infection is resolved and, for reasons that are not completely understood, sometimes comes back as shingles later in life. The most common complication of shingles, especially in people over the age of 60, is post-herpetic neuralgia, a condition that causes severe, unremitting pain that sometimes lasts for years.