Live Zoster Shot May Be Safe in People With Mild Immunosuppression

By Anne Harding

February 10, 2020

NEW YORK (Reuters Health) - Live attenuated varicella zoster vaccine appears to be safe for individuals with mild immunosuppression, according to new findings.

Among more than 1,700 individuals who inadvertently received the shot while immunosuppressed, two cases of varicella zoster virus (VZV)-related disease developed, and neither patient required hospitalization, Dr. Helen I. McDonald of the London School of Hygiene and Tropical Medicine and colleagues found.

"We hope this finding will encourage vaccination of people with mild immunosuppression, who do not meet the current thresholds for contraindication and who are likely to significantly benefit from vaccination given their higher risk of complications if they develop shingles," Dr. McDonald told Reuters Health by email.

Since 2013, the U.K. has recommended herpes zoster vaccination for immunocompetent individuals in their 70s, Dr. McDonald and her team note in BMJ Open. There have been case reports of people with severe immunosuppression dying of vaccine-related disease after receiving the shingles vaccine, they add.

To better understand risks associated with immunosuppression, the authors reviewed electronic health records for more than 168,000 patients who were age-eligible for the vaccine in 2013-2017.

Among 1,742 who received the shingles vaccine while immunosuppressed, usually because they were on chemotherapy or taking immunosuppressant medications, two cases of shingles occurred. None of the patients were hospitalized or developed encephalitis.

"This suggests that severe illness following live vaccination against shingles is rare, even among people with immunosuppression," Dr. McDonald said.

"In our study, doctors may have carefully selected which immunosuppressed patients to vaccinate and when, so this doesn't mean that it is safe to vaccinate all patients with severe immunosuppression, and the current guidance should continue to be followed," she added.

"The case studies remind us that the consequences of live vaccination in severe immunosuppression can be fatal," Dr. McDonald said. "But it is reassuring that severe illness following live shingles vaccination is rare among patients who meet the definition of severe immunosuppression."

"We are now planning a larger study to investigate the burden of zoster disease and the safety of live vaccination according to the underlying cause of immunosuppression, to inform a review of the current guidelines on contraindications to live zoster vaccination, and decisions about which patients might benefit most from the recombinant zoster vaccine when it is available," Dr. McDonald said.

The study did not have commercial funding.

SOURCE: BMJ Open, online January 29, 2020.