P-1444. Safety and Long-Term Immunogenicity of Yellow Fever Vaccine in Elderly Korean Travelers: A Retrospective Cohort Study

Abstract Background Yellow fever (YF) remains endemic in parts of Africa and South America. Although the YF vaccine, derived from the 17D strain, is highly effective, concerns remain regarding its safety and immunogenicity in elderly individuals over 60 years old. WHO classifies YF vaccination in this age group as a relative contraindication, recommending that healthcare providers carefully weigh the risks and benefits with recipients. As international travel from Korea to YF-endemic areas rises, including among older adults, data are needed to guide vaccination in this population.Figure 1.Comparison of (A) Humoral (YFV-gE Ab Titer) and (B) Cellular (IFN-γ ELISPOT) Immune Response Between in