Impact of the SARS-CoV-2 Pandemic on Routine Immunization Services: Evidence of Disruption and Recovery From 169 Countries and Territories

Background: The SARS-CoV-2 pandemic has revealed the vulnerability of immunization systems worldwide, although the scale of these disruptions has not been described at a global level. Methods: This report synthesized data representing 169 countries and territories. Data sources included administered vaccine dose data from January-December 2019 and 2020, WHO Regional office reports, and the WHO-led pulse survey administered in April and June 2020. Results were expressed as frequencies and proportions of respondents or reporting countries. Vaccine doses administered data were weighted by the population of surviving infants per country. Findings: A decline in the number of DTP3 and MCV1 doses administered in the first half of 2020 was noted. The nadir was observed in April 2020, when 35% fewer DTP3 doses were administered globally, ranging from 10% in Africa to 58% in South East Asia. Recovery of vaccinations began by June 2020 and continued into late 2020. WHO regional offices reported significant disruption to routine vaccination sessions in April 2020, related to interrupted vaccination demand, and supply, including reduced availability of the health workforce. Pulse survey analysis revealed that 69% of countries experienced disruption in outreach services compared to 44% countries with disrupted fixed-post immunization services.   Interpretation: The marked magnitude and global scale of immunization disruption evokes the dangers of vaccine-preventable disease outbreaks in the future. Trends indicating partial resumption of services highlight the urgent need for ongoing assessment of recovery, catch-up vaccination strategy implementation for vulnerable populations, and ensuring vaccine coverage equity and health system resilience. Funding: World Health Organization and U.S. Agency for International Development (USAID). Conflict of Interest: We declare no competing interests.