Enhancing Herpes Zoster Vaccination Rates Among Oncology Outpatients: Impact of an In-House Vaccination Initiative.

Background: Herpes zoster (HZ) poses significant risks to immunocompromised individuals, particularly cancer patients receiving systemic therapies. The recombinant zoster vaccine (RZV, Shingrix®) provides strong and durable protection against HZ and its complications. Nevertheless, vaccination coverage remains low, mainly due to limited awareness among patients and healthcare providers and logistical barriers to vaccine access and delivery. Materials and Methods: We conducted a single-center quality improvement (QI) project to enhance RZV uptake among oncology outpatients receiving systemic therapy. Following the Plan-Do-Study-Act (PDSA) model, baseline HZ vaccination coverage was assessed, and an in-house vaccination campaign was implemented. Vaccination rates were monitored every two months over a 14-month period. Results: At baseline, only 5.4% (24/446) of patients had received RZV. After 14 months, 365 patients were evaluated for vaccination: 200 (55%) were vaccinated, 134 (37%) were ineligible, and 31 (8%) refused RZV. The overall vaccination rate increased from 5.4% to 44%. Reported adverse events were mild and primarily local reactions, confirming the vaccine's favorable safety profile in this population. Conclusions: This real-world QI initiative demonstrates that an in-house vaccination strategy embedded within oncology services can substantially improve RZV coverage and patient engagement. The approach highlights the key role of oncology teams in leading preventive interventions for immunocompromised patients. By integrating vaccination into routine cancer care, institutions can overcome traditional organizational barriers and align with current ASCO and ESMO recommendations for comprehensive patient protection.