Global Status of Adult Immunization Post COVID-19 Pandemic

Background: Historically, immunization programmes have focused on infants, children, and women of reproductive age. COVID-19 vaccination prompted countries to vaccinate adults. This manuscript provides a global overview of adult immunization post COVID-19 pandemic. Methods: We summarized WHO Strategic Advisory Group of Experts on Immunization (SAGE) recommendations by adult group and analyzed the data reported in 2024 (2023) by WHO Member States (MS) via the WHO/UNICEF electronic Joint Reporting Form on Immunization (eJRF) on national immunization schedules, and from other sources by WHO region and income group. Results: WHO policy recommendations exist for most of the licensed vaccines targeting adults; however, the inclusion in national immunization schedules is higher in high-income (HICs) and middle-income (MICs) countries. For pregnant women, 90% of MS reported vaccination against COVID-19 (65% in low-income countries [LICs]), 63% against tetanus-containing vaccines (73% in LICs), 57% against influenza (4% in LICs), and 21% against pertussis-containing vaccines (all MICs and HICs). For health workers, 91% against COVID-19 (92% in LICs), 59% against influenza (4% in LICs), and 25% against hepatitis B (10% in LICs). For adults with chronic diseases, COVID-19 vaccination data were not available, 58% against influenza, and 23% against pneumococcal disease. For older adults, more than 90% of MS across all income groups reported COVID-19 vaccination, 59% against influenza (8% of LICs versus 89% of HICs), 17% against pneumococcal, and 7% against herpes zoster. Conclusion: The disparities in adult immunization policies across income groups highlight the need to improve access and strengthen vaccination efforts. A life course approach is essential to maximize the full potential of immunization across all ages.