Vaccine delivery innovation improves accessibility and reduces costs for developing countries by 76 per cent

Access, amongst other approaches like communication, is crucial to achieving vaccine equity in developing countries
- Niccolò F. Meriggi, International Growth Centre
Sierra Leone vaccination card 747x560
Sierra Leonean holds out COVID-19 vaccination card to the camera Michael Duff

A solution which increases vaccine uptake among rural populations in developing countries, and is 76 per cent cheaper than the average cost of similar interventions, has been developed with researchers from the International Growth Centre (IGC) based at LSE.

The 2022 study, “Last-mile delivery increases vaccine uptake in Sierra Leone”, was conducted one year into Sierra Leone’s COVID-19 vaccine roll-out. The simple and widely applicable intervention improved COVID-19 vaccine uptake among target rural communities by 26 percentage points within 48-72 hours of the intervention being introduced, and vaccination counts increased sevenfold.

With the Sierra Leone Ministry of Health and Sanitation, and international NGO, Concern Worldwide, the research team conducted a randomised controlled trial with just over 20,000 Sierra Leoneans over age 12, living in 150 rural towns outside Sierra Leone’s national clinic network. Health workers took vaccines to communities where they set up temporary vaccination sites, provided information about the vaccine with community members, and administered it, augmenting the reach of existing clinic infrastructures.

At the time, only six to nine per cent of the adults who took part in the intervention were immunised. Researchers examined whether improved access to the vaccine would increase this figure, after finding high levels of vaccine acceptance in 10 low- and middle-income countries in a previous study in 2021. By December 2022, Sierra Leone reached the WHO’s global target to immunise 70% of its adult population against COVID-19, and in March 2023, 7.8 million vaccine doses had been delivered.

The model has the potential to be replicated across developing countries with large rural populations, and similar transport, community, and infrastructure set-ups. As transportation to reach villages accounted for a large share of this model’s costs, including multiple maternal and child health interventions on the same trip in future would further lower costs per person treated.

The research team has since been awarded funds from the IGC and the Social Science Research Council. The grants will be used to expand the model in this paper to a bundle of health products and services, including additional vaccines and maternal and child health interventions, and further explore its feasibility and cost-effectiveness. The first bundle will include the COVID-19 vaccine, HPV vaccine for girls aged 10-12, and routine immunisations for children aged 0-6.

Niccolò F. Meriggi, principal investigator said: “Our research shows that access was a binding constraint to the COVID-19 vaccination campaign in remote areas of Sierra Leone. Access, amongst other approaches like communication, is crucial to achieving vaccine equity in developing countries, and will likely be relevant to the new malaria vaccine roll-out and other health products and services.”

Behind the article

The authors of the research are:

Niccolò F. Meriggi, Country Economist, Sierra Leone, International Growth Centre

Ahmed Mushfiq Mobarak, Lead Academic, Bangladesh, International Growth Centre

Maarten Voors, Researcher, International Growth Centre


International Growth Centre

The IGC works with policymakers in developing countries to promote inclusive and sustainable growth through pathbreaking research. It is a global research centre with a network of world-leading researchers, country teams across Africa, South Asia and the Middle East, and a set of global policy initiatives. Based at LSE and in partnership with the University of Oxford, we are majority funded by the UK Foreign, Commonwealth and Development Office (FCDO).


Contact information:

Annelise Andersen, Head of Communications, IGC