511 Herpes zoster vaccine effective in older adults

August 21, 2017

written by Brian R McAvoy.

Clinical question
Compared with placebo or no vaccine, how effective is vaccination for preventing herpes zoster in older adults?

Bottom line
Moderate-quality evidence suggests, in persons of 60 years of age or older, the herpes zoster vaccine reduced the incidence of herpes zoster for at least 3 years post vaccination (NNT* 50). The vaccinated group had a higher incidence of mild-to-moderate intensity adverse events (mild-to-moderate symptoms at the injection site). Refrigerated vaccines caused fewer injection site adverse effects than frozen vaccines. The injection of the vaccine into the muscle caused fewer adverse effects than when it was injected subcutaneously. (*NNT = number needed to treat to benefit 1 individual.)

Caveat
All included studies were conducted in high-income countries and included only healthy, elderly, Caucasian participants (age >60 years) with no immunosuppressive problems. Pharmaceutical companies that produce the vaccines funded all of the included studies.

Context
The natural process of ageing is associated with a reduction in cellular immunity, and this predisposes older people to herpes zoster. Vaccination with an attenuated form of varicella zoster virus activates specific T-cell production, avoiding viral reactivation.

Cochrane Systematic Review
Gagliardi AMZ et al. Vaccines for preventing herpes zoster in older adults. Cochrane Reviews, 2016, Issue 3. Art. No.: CD008858.DOI: 10.1002/14651858. CD008858.pub3. This review contains 13 studies involving 69,916 participants.

Pearls are an independent product of the Cochrane primary care group and are meant for educational use and not to guide clinical care.