391 “Varicella vaccination strategies for refugees: systematic or targeted approaches?”

Abstract EP2.1, e-Poster Terminal 2, September 3, 2025, 10:35 - 11:00 Aims The varicella-zoster virus (VZV) can cause severe complications in non-immune adults, including varicella pneumonia. Among migrant populations, access to preventive care, such as vaccination, remains a public health challenge. The Swiss vaccination plan recommends that adults under 40 years of age without a clinical history of varicella be vaccinated. However, refugees are often unaware of their vaccination status or past infections, as varicella is typically acquired in childhood. Our unit, part of the Geneva University Hospitals (HUG), is responsible for vaccinating refugees assigned to the canton of Geneva. Since hospital admissions for varicella-related complications appear to be rare among refugees, we focused our VZV vaccination strategy on women of childbearing age due to the significant fetal risks associated with varicella infection during pregnancy. Methods Between June 2021 and December 2024, 249 women aged 18–40 years underwent systematic anti-VZV IgG screening before vaccination. A descriptive analysis of serological data was performed, along with an economic evaluation comparing the costs of serological testing (37.80 CHF/test) with systematic vaccination using the Varilrix vaccine (two doses, 62.50 CHF/dose). Results Among the participants, 29% were from Turkey, 23% from Afghanistan, and the remaining individuals came from 30 different countries. Immunity to VZV was confirmed in 231 women (92.8%), while 7.2% were seronegative. Seronegativity rates were consistent across all origins. Conclusion These findings support a targeted VZV vaccination strategy in the refugee population, preventing unnecessary vaccinations and reducing healthcare costs while maintaining personalized care. The absence of significant serological differences between geographic origins justifies a universal approach for this group. This strategy underscores the value of precision medicine in public health, ensuring efficient resource allocation, minimizing unnecessary interventions, and better addressing the needs of vulnerable populations.