New clinical findings have found patients with prior herpes zoster ophthalmicus (HZO) were more likely to experience a recurrence in the first 8 weeks after receiving a shingles vaccine, compared with the 8 weeks that followed.
The data was presented during last month’s Association for Research in Vision and Ophthalmology (ARVO) annual meeting.
Give me some background first.
Some context: HZO is reactivation of the varicella zoster virus along the ophthalmic branch of the trigeminal nerve. It can cause a range of ocular complications, from keratitis and uveitis to optic neuropathy and permanent vision loss.
A few facts to know:
- HZO accounts for roughly 10 to 20% of all herpes zoster cases
- Ocular involvement develops in about half of all patients
- With a lifetime shingles risk of about one in three in the U.S., this is a population eyecare providers (ECPs) see routinely
And to prevent this?
The live zoster vaccine has been replaced by the recombinant zoster vaccine (Shingrix), which the CDC's Advisory Committee on Immunization Practices recommends as the preferred option for immunocompetent adults aged 50 and older.
But here's the issue: Few existing studies have examined recurrence risk in patients with pre-existing HZO who go on to receive a shingles vaccine—leaving an open clinical concern about whether vaccination might trigger reactivation in eyes that have already been affected.
Now, talk about the study.
Researchers at Kaiser Permanente Northern California ran a retrospective cohort study using their integrated health system records.
The question: Is there an increased risk of recurrent HZO in the period immediately following shingles vaccination?
The setup: Researchers used a self-controlled risk interval (SCRI) analysis, where each patient served as their own control.
- The risk interval was defined as days 1 to 56 after a dose of the shingles vaccine, compared against a self-controlled interval of days 57 to 112 after the same dose.
Who was included in the study?
The cohort included 10,018 patients aged 50 and older with an incident HZO diagnosis between 2010 and 2023.
To make the cut, patients needed to have:
- An incident HZO diagnosis on record
- Subsequently received either the live zoster vaccine, the recombinant zoster vaccine, or both
Of the full cohort, 2,900 went on to receive shingles vaccination during the study window.
Findings?
Across the 112 days following any shingles vaccination, 38 cases of recurrent HZO were identified.
The kicker: Of those 38 recurrences, 34 (89%) had pre-existing ocular involvement before vaccination, compared with 1,193 (42%) of the patients who did not recur (p<0.001).
Time from incident HZO to first vaccination also differed between the groups, with a median of
- 309 days (range: 185 to 625) in the recurrence group (p<0.001)
- 991 days (range: 451 to 1,900) in the non-recurrence group (p<0.001)
Tell me more.
In the SCRI analysis, the incidence rate of HZO recurrence was higher during the days 1 to 56 risk interval than during the days 57 to 112 control interval, with an incidence rate ratio (IRR) of 2.05 (p=0.048).
Worth noting: Recurrence in the first 8 weeks after vaccination ran at roughly twice the rate of the subsequent 8 weeks, though the overall absolute incidence remained low.
Limitations?
As this was an abstract presentation, the full peer-reviewed methods and additional sensitivity analyses were not made available.
Among the other considerations:
- The study population was drawn from a single integrated health system, which limited how broadly the absolute rates generalize
- Live zoster and recombinant zoster vaccine doses were combined in the primary analysis—the abstract did not break out vaccine-specific risk
- The study’s self-controlled design
Expert opinion?
The authors concluded that the findings support vigilance around the timing of shingles vaccination in patients with pre-existing HZO, particularly those vaccinated soon after their initial diagnosis.
Anything else?
One finding that stands out: The recurrence group was vaccinated about two and a half times sooner after their initial HZO episode than the non-recurrence group.
- That timing gap, paired with the 89% rate of pre-existing ocular involvement, points to a window where vaccination may overlap with still-active disease.
Why that matters: The ACIP currently recommends an 8-week interval between Zostavax and a Shingrix dose, but there is no equivalent guidance on how long to wait after an incident HZO episode before vaccinating.
The findings here raise the question of whether such an interval should be considered.
Take home.
Clinicians may want to take a closer look at vaccination timing in this population and counsel patients on what symptoms to watch for in the weeks immediately following a dose.