Impact of the COVID-19 pandemic on routine childhood immunisation in Colombia.

Objective: To assess the impact of the COVID-19 pandemic on routine childhood vaccination coverage in Colombia by age group, rural/urban residence, state and vaccine type.

Design: Ecological study of official monthly vaccination records.

Setting: Vaccination records from the Colombian Ministry of Health (March-October 2019 and 2020).

Participants: Aggregated data for Colombian children (<12 months, n=676 153; 12-23 months, n=700 319; and 5 years, n=734 295) participating in the Expanded Program on Immunization.

Main Outcome Measures: Proportion of eligible population receiving vaccination.

Results: Vaccination coverage showed an overall decline of approximately 14.4% from 2019 to 2020 (2019 coverage=76.0, 2020 coverage=61.6%). The greatest reduction in proportion vaccinated was observed in children <12 months of age for pneumococcal vaccine (second dose) (2019 coverage=81.4%; 2020 coverage=62.2%; 2019-2020 absolute difference, 19.2%; 95% CI 14.8% to 23.7%). For children aged 12-23 months, the proportion vaccinated for yellow fever declined by 16.4% (12.4% to 20.9%) from 78.3% in 2019 to 61.8% in 2020. Among children 5 years of age, the biggest decrease occurred for the oral polio vaccine (second dose), with a difference of 11.4% (7.1% to 15.7%) between 2019 and 2020 (73.1% and 61.7% for 2019 and 2020). We observed a statistically significant effect on vaccine coverage in rural versus urban areas for children <12 months and 5 years of age.

Conclusions: Reduced uptake of immunisations during the COVID-19 pandemic poses a serious risk of vaccine-preventable disease outbreaks. Colombia and other middle-income countries need to continue to monitor immunisation programme coverage and disease outbreaks at the national and subnational levels and undertake catch-up vaccination activities.