Herpes zoster admissions: The majority of patients are not immunised

Abstract

Herpes zoster (HZ) is usually self-limiting, however, can lead to significant morbidity, especially in the immunosuppressed or elderly individual. The adjuvant recombinant subunit HZ vaccine Shingrix has been on the market since 2017 and can reduce the risk of varicella zoster virus (VZV) reactivation.¹

To date, we report a total of 300 HZ admissions to our tertiary care Dermatology department in 2023 and 2024, of which only two patients were fully immunised with the zoster vaccine, meaning having received the two full doses. One was a 57-year-old female taking fingolimod for relapsing-remitting multiple sclerosis (MS), and the other was a 76-year-old male who was taking low-dose prednisolone (2.5 mg once daily) for polymyalgia rheumatica. All other admitted patients had not or had only been partially immunised with the HZ vaccine (one patient). Physicians should be aware of the various drug classes which may increase the risk of VZV reactivation and consider recommending immunisation to patients taking any of these. Fingolimod, for example, is a sphingosine 1-phosphate receptor modulator which inhibits the migration of CD4-naive T cells and central memory T cells from lymphoid organs; it can cause lymphopenia and is licensed for the treatment of recurrent remittent forms of MS.^{2, 3} Other examples of the same drug group are ozanimod and ponesimod. Dimethyl fumarate and diroximel fumarate are further options for the treatment of MS and are also known to increase the risk of VZV reactivation. Their direct mode of action is not fully understood; however, they are thought to modify immune cell migration and can cause lymphopenia.⁴ Other immunosuppressants such as cladibrine, Janus kinase inhibitors and corticosteroids are also known to increase the risk of VZV reactivation considerably.^{5, 6} Given the notable lack of fully immunised patients presenting to our department, we recommend discussing this risk of HZ with all patients at risk (adults aged 50 years and older, as well as adults aged 18 years and older who are or will be at increased risk of HZ due to immunodeficiency or immunosuppression) and immunisation should be considered.

Mina M. Raahimi: Conceptualisation; visualisation; writing. Martin Hartmann: Supervision.

The authors declare no conflict of interest.

Not applicable.