BACKGROUND: Herpes zoster (HZ) incidence is linked to immunosuppression. Patients with psoriasis or psoriatic arthritis (PsA) on systemic therapy might be at an increased risk for HZ.
OBJECTIVE: To assess HZ risk in patients with psoriasis and PsA by systemic treatment and provide recommendations regarding HZ vaccination.
METHODS: A systematic literature search was performed for HZ in patients with psoriasis and PsA. HZ vaccination guidelines were reviewed, and the medical board of the National Psoriasis Foundation made consensus recommendations in psoriasis and PsA patients using graded evidence.
RESULTS: In total, 41 studies met inclusion criteria. Systemic corticosteroids (strong, 1), tofacitinib (strong, 1), and combination therapy with biologic and conventional synthetic disease-modifying antirheumatic drugs (weak, 2a) carry increased HZ risk while monotherapy does not. There is insufficient evidence to determine risk with interleukin 12/23, 17, and 23 inhibitors or apremilast (weak, 2a). Recombinant zoster vaccine is recommended for all psoriasis and PsA patients >50 years old and patients <50 years old on tofacitinib, systemic steroids, or combination systemic treatment. Vaccination of patients <50 years old on other systemic therapies may be considered on a case-by-case basis.
CONCLUSIONS: There was significant heterogeneity between studies.
CONCLUSIONS: HZ risk depends on disease severity and treatment class. Recombinant zoster vaccine should be given to all psoriasis and PsA patients >50 years old and younger patients at increased risk.

The three-fingered toxin family and more precisely short-chain α-neurotoxins (also known as Type I α-neurotoxins) are crucial in defining the elapid envenomation process, but paradoxically, they are barely neutralized by current elapid snake antivenoms. This work has been focused on the primary structural identity among Type I neurotoxins in order to create a consensus short-chain α-neurotoxin with conserved characteristics. A multiple sequence alignment considering the twelve most toxic short-chain α-neurotoxins reported from the venoms of the elapid genera Acanthophis, Oxyuranus, Walterinnesia, Naja, Dendroaspis and Micrurus led us to propose a short-chain consensus α-neurotoxin, here named ScNtx. The synthetic ScNtx gene was de novo constructed and cloned into the expression vector pQE30 containing a 6His-Tag and an FXa proteolytic cleavage region. Escherichia coli Origami cells transfected with the pQE30/ScNtx vector expressed the recombinant consensus neurotoxin in a soluble form with a yield of 1.5 mg/L of culture medium. The 60-amino acid residue ScNtx contains canonical structural motifs similar to α-neurotoxins from African elapids and its LD50 of 3.8 µg/mice is similar to the most toxic short-chain α-neurotoxins reported from elapid venoms. Furthermore, ScNtx was also able to antagonize muscular, but not neuronal, nicotinic acetylcholine receptors (nAChR). Rabbits immunized with ScNtx were able to immune-recognize short-chain α-neurotoxins within whole elapid venoms. Type I neurotoxins are difficult to isolate and purify from natural sources; therefore, the heterologous expression of molecules such ScNtx, bearing crucial motifs and key amino acids, is a step forward to create common immunogens for developing cost-effective antivenoms with a wider spectrum of efficacy, quality and strong therapeutic value.