Learning from the COVID-19 pandemic to strengthen routine immunization systems
Authors: Kate Causey, Jonathan F. Mosser
Journal: PLoS Medicine (2022)

In the final months of 2021, deaths due to the Coronavirus Disease 2019 (CAU : PleasenotethatCOVID OVID-19) surpassed 5 million globally [1].Available data suggest that even this staggering figure may be a substantial underestimate of the true toll of the pandemic [2].Beyond mortality, it may take years to fully quantify the direct and indirect impacts of the COVID-19 pandemic such as disruptions in preventive care services.In an accompanying research study in PLOS Medicine, McQuaid and colleagues report on the uptake of routine childhood immunizations in 2020 in Scotland and England during major pandemic-related lockdowns [3].This adds to a growing body of literature quantifying the impact of the COVID-19 pandemic on routine health services and childhood immunization [4,5], which provides important opportunities to learn from early pandemic experiences as immunization systems face ongoing challenges.McQuaid and colleagues compared weekly or monthly data on vaccine uptake in Scotland and England from January to December of 2020 to the rates observed in 2019 to estimate the changes in uptake before, during, and after COVID-19 pandemic lockdowns in each country.The authors included 2 different preschool immunizations, each with multiple doses.They found significantly increased uptake within 4 weeks of eligibility during the lockdown and postlockdown periods in Scotland for all 5 vaccine dose combinations examined: During lockdown, percentage point increases ranged from 1.3% to 14.3%.In England, there were significant declines in uptake during the prelockdown, lockdown, and postlockdown periods for all 4 vaccine dose combinations examined.However, declines during lockdown were small, with percentage point decreases ranging from -0.5% to -2.1%.Due to the nature of the data available, the authors were unable to account for possible seasonal variation in vaccine delivery, control for important individual-level confounders or effect modifiers such as child sex and parental educational attainment, or directly compare outcomes across the 2 countries.These findings stand in contrast to the documented experience of many other countries, where available data suggest historic disruptions in routine childhood vaccination coverage, particularly during the first months of pandemic-related lockdowns [5,6].Supply side limitations such as delayed shipments of vaccines and supplies [7], inadequate personal protective equipment [8], staff shortages [9], and delayed or canceled campaigns and introductions [9] threatened vaccine delivery.Furthermore, fear of exposure to COVID-19 at vaccination centers [10], misinformation about vaccine safety [8], and lockdown-related limitations on travel to facilities [9,10] reduced demand.In polls of country experts conducted by WHO, UNICEF, and Gavi, the Vaccine Alliance throughout the second quarter of 2020, 126 of 170 countries reported at least some disruption to routine immunization programs [10,11].Global estimates suggest that millions more children missed doses of important vaccines than would have in the absence of the COVID-19 pandemic [5,6].While many vaccine programs showed