Global effects of COVID-19 on routine childhood immunizations

Abstract

In 2020 the COVID-19 pandemic and policies to reduce social contact have impacted health service delivery across the world. Interruptions in routine childhood immunizations without catch-up vaccination are likely to lead to outbreaks of vaccine-preventable diseases. We estimated the short-term effects of COVID-19 on vaccine coverage for the first does of measles-containing-vaccine (MCV1) and the third dose of diphtheria-tetanus-pertussis (DTP3) in 2020 in 204 countries and territories. Utilizing mobility data from mobile phone users as a proxy for COVID-19 disruptions and various sources of vaccine coverage data including caregiver surveys, administrative data, and electronic medical records, we implemented a 2-stage spline modelling approach. For the second half of 2020 we generated estimates of vaccine disruptions based on projections of the COVID-19 pandemic and continued mobility reductions. Paired with estimates of expected 2020 vaccine coverage in the absence of COVID-19, we calculated the estimated 2020 coverage of DTP3 and MCV1 among 1-year-olds. In the absence of COVID-19, we estimated that 83.9% and 86.3% of children under 1 would receive vaccinations for DTP3 and MCV1; we expect COVID-19 related health-delivery interruptions to decrease 2020 global coverage to 72.7% (95% UI 69.1 – 74.7) and 72.7% (95% UI 69.2 – 74.8) for each of these antigens, far below the 2020 Global Vaccine Action Plan goal of 90% coverage. Disruptions are nearly universal, affecting nearly every country, with the highest disruptions in South Asia, Latin American and Caribbean, and High-income countries. In order to prevent outbreaks of measles and other vaccine-preventable diseases, national governments must act quickly to restore routine immunization programs for children and perform catch-up vaccinations for those missing vaccines including adapting data information systems to capture these efforts.