Impact of the SARS-CoV-2 pandemic on routine immunisation services: evidence of disruption and recovery from 170 countries and territories

Abstract

Background: The SARS-CoV-2 pandemic has revealed the vulnerability of immunisation systems worldwide, although the scale of these disruptions has not been described at a global level. This study aims to assess the impact of COVID-19 on routine immunisation using triangulated data from global, country-based, and individual-reported sources obtained during the pandemic period.

Methods: This report synthesised data from 170 countries and territories. Data sources included administered vaccine-dose data from January to December, 2019, and January to December, 2020, WHO regional office reports, and a WHO-led pulse survey administered in April, 2020, and June, 2020. Results were expressed as frequencies and proportions of respondents or reporting countries. Data on vaccine doses administered were weighted by the population of surviving infants per country.

Findings: A decline in the number of administered doses of diphtheria-pertussis-tetanus-containing vaccine (DTP3) and first dose of measles-containing vaccine (MCV1) in the first half of 2020 was noted. The lowest number of vaccine doses administered was observed in April, 2020, when 33% fewer DTP3 doses were administered globally, ranging from 9% in the WHO African region to 57% in the South-East Asia region. Recovery of vaccinations began by June, 2020, and continued into late 2020. WHO regional offices reported substantial 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 45 (69%) of 65 countries showed disruption in outreach services compared with 27 (44%) of 62 countries with disrupted fixed-post immunisation services.

Interpretation: The marked magnitude and global scale of immunisation 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: US Agency for International Development.

Figure 1

Proportion of countries reporting pandemic-related disruption to routine immunisation sessions, health workforce availability, vaccine supply, and demand for immunisation services in April, 2020 Analysis of data collected by WHO regional offices from their respective member states. Indicators not included in regional data-collection instruments might be underestimated. Vaccine demand was not systematically collected for AFR, EMR, EUR, and SEAR. Vaccine supply was not systematically collected for EMR. Health workforce availability was not systematically collected for EMR and EUR. Results for these indicators for these regions may be an underestimate. Data were sourced from WHO regional office reports. WPR was not represented because the data were not available. N represented the total number of countries in the respective region. AMR=region of the Americas. AFR=African region. EMR=Eastern Mediterranean region. EUR=European region. SEAR=South-East Asia region. WPR=Western Pacific region.

Figure 2

Weighted mean relative difference in DTP3 and MCV1 administered from January, 2020, to December, 2020, compared globally with 2019 and by WHO Region Mean relative difference in DTP3 (A) and MCV1 (B) administered in 2020 compared with 2019, weighted by surviving infants. Analysis of administrative data of vaccine doses given, and data from the UN Population Division for surviving infants by country or region. Numbers in parentheses indicate number of countries with available data for the respective month. AMR=region of the Americas. AFR=African region. EMR=Eastern Mediterranean region. EUR=European region. SEAR=South-East Asia region. WPR=Western Pacific region. DTP3=third dose of diphtheria–pertussis–tetanus-containing vaccine. MCV1=first dose of measles-containing vaccine.

Figure 3

Urgent actions for sustaining immunisation activities globally