Closing the gap in childhood immunisation after the pandemic

Childhood immunisations are among the most cost effective, equitable, and successful interventions of all times. The World Health Organization’s expanded programme on immunisation has ensured that routine childhood immunisations are available in every country, and vaccination is believed to save around three million lives annually.1 Eligible low and middle income countries have been supported by Gavi (the Vaccine Alliance) and Unicef to improve access to new and underused vaccines.

Vaccination coverage increased substantially between 2000 and 2019, averting about 37 million deaths globally during that period. The global coverage of DTP3 (three doses of the combined diphtheria, pertussis, and tetanus vaccine), third polio dose, and first measles dose was 84%-86% globally by 2019, and coverage of the second dose of measles vaccine increased from 42% to 71% from 2010 to 2019. Coverage of more recently recommended vaccines such as rotavirus, pneumococcal conjugate, rubella, and hepatitis B also increased.23

Vaccination coverage had plateaued before the covid-19 pandemic began in 2020, however, and cracks had appeared in the once successful implementation programme. In 2019 alone, 19.7 million children, particularly in low and middle income countries did not receive their third dose of DTP, and 70% of these had not received a single dose of DTP vaccine (“zero dose” children). In Africa the dropout rate between the first and third dose of DTP was estimated at 9%. Between 2010 and 2019, increasing numbers of children received no immunisations—most of whom were in Gavi supported countries in WHO’s Africa (increase from 6.1 million to 6.8 million), Western Pacific (0.9 million to 1.2 million), and Americas regions (0.5 million to 1.5 million)—because of a failure to deliver services to the hardest to reach, “last mile” populations. As countries reached middle income levels, those previously supported by Gavi found themselves with limited access to vaccines.24

The pandemic and ensuing restrictive preventive measures exposed weaknesses in all health systems. It was deeply damaging for primary healthcare services, particularly routine immunisation programmes globally. Many countries, especially those with low or middle incomes, experienced interruptions in routine immunisation campaigns and services, restrictions in supply and access to vaccines (for example, shortages of BCG vaccine because of increased unproved use for covid-19), shortages of healthcare staff and personal protective equipment, and disruptions in access to vaccination services.

Vaccine hesitancy increased as a result of rampant misinformation on vaccine safety and development.56 All this quickly reduced vaccine demand and coverage, allowing breakthrough outbreaks. Measles outbreaks are on the rise worldwide—incidence increased by 79% globally in the first two months of 2022 compared with the same time in 2021,7 and at least 21 outbreaks were reported, especially in Africa and the eastern Mediterranean.8 Global progress in polio eradication has been halted by fresh outbreaks, triggering major vaccination campaigns in Africa and elsewhere.9