A shingles vaccine you have to take twice, recommended a decade earlier

Herpes zoster — shingles — is a **localised, usually painful skin eruption
from reactivation of the varicella zoster virus** you caught as chickenpox.

It is not rare:

The complication that matters

Postherpetic neuralgia — **pain persisting at least 90 days after the rash
resolves** — is the most common complication, and occurs in **10% to 13% of
cases in people over 50.** The risk rises with age.

Between one in ten and one in eight. The rash heals in weeks; the pain can last
months.

What changed in 2017

On 20 October 2017 the FDA approved Shingrix — **recombinant zoster
vaccine**, a 2-dose subunit vaccine of recombinant glycoprotein E with a
novel adjuvant. Two 0.5 mL doses, intramuscular, 2–6 months apart.

On 25 October — five days later — **ACIP recommended it for immunocompetent
adults aged ≥50.**

Two differences from what came before:

A decade earlier, and twice the appointments.

Moving to 50 matters because that is where incidence starts climbing and where
postherpetic neuralgia is already running at 10–13%. The two-dose schedule is
the cost: a vaccine only works if the second dose happens, and that is a real
problem for anything administered months apart to people who feel well.

What it was replacing

**Zostavax coverage had increased every year since licensure — by 2016, 33% of
adults aged ≥60 reported receiving it.**

A third, after a decade, with a single dose. That is the number the two-dose
schedule has to beat.

**ACIP considered the new vaccine alongside the existing recommendations to
develop a policy that would be safe and reduce disease burden** — which is why
this report is a supplement to the 2008 recommendations rather than a
replacement of them: both vaccines remained in use, with guidance for each.

Source: Centers for Disease Control and Prevention, MMWR.