The virus that causes chickenpox, varicella zoster, doesn’t confine its activity to childhood. For reasons that remain unclear, it can re-emerge in older age as the rash called herpes zoster, more commonly known as shingles. Just as you can get chickenpox only once, usually you also have shingles only once. But that “once” can translate into chronic, unbearable pain if a complication known as postherpetic neuralgia develops. This pain, a burning nerve pain severe enough to disrupt sleep, can last for years.
That’s why people who are eligible for the shingles vaccine should get one. But who are those people?
The short answer is, almost anyone age 60 and over. The U.S. Food and Drug Administration has approved this vaccine only for this age group because researchers have no evidence yet that it’s effective in younger groups. It makes sense because one of the risk factors for developing shingles is . . . being over 60. Another risk factor is having had chickenpox before age 1.
The shingles vaccine is not, however, a substitute for the childhood vaccines against chickenpox.
Some people in the over-60 age group should not get the shingles vaccine. Avoid this vaccine if any of the following applies to you:
- You’ve had a life-threatening allergic reaction to gelatin or the antibiotic neomycin. The vaccine contains other ingredients, so if you’re deathly allergic to something, check the ingredients list.
- You’re taking drugs that suppress the immune system or have a disease that does, such as HIV, because this vaccine is a live-virus vaccine.
- You have tuberculosis.
- You are or might become pregnant, an unlikely possibility in the 60+ age group.
- You are moderately to severely ill, including have a fever over 101.3 F. Wait to get the vaccine until you’re better.
Can you get this vaccine if you’ve already had the shingles? Sure, even though you’re not likely to get shingles again. You can also get this vaccine while receiving the influenza vaccine.
Like any vaccine or other medical intervention, the shingles vaccine can have side effects and carry risk. The most common side effects are pain and swelling at the injection site and headache. One large research study of the safety of the vaccine found no difference in rates of negative events between the vaccinated group and the group that received a placebo (a dummy injection). A substudy within that study, however, found a slightly higher rate of serious adverse events in the real vaccine group compared to placebo (1.9% vs. 1.3%). The data did not indicate that the events were vaccine-related.
The effectiveness of this vaccine depends on the outcome in question. Studies indicate that it reduces your risk of getting shingles by about 50%. If you do get shingles, the vaccine is linked to fewer days of pain during the outbreak and shorter periods of pain for people who go on to develop postherpetic neuralgia.