New systems map can help overcome difficulties in vaccinating hard-to-reach communities

A major obstacle for COVID-19 vaccination programs to achieve higher and more equitable vaccine coverage throughout the world is vaccinating hard-to-reach communities.

  • 23 June 2021
  • 3 min read
  • by Sarah Rebbert (PHICOR)
Gavi/Africa/Simon Davis
Gavi/Africa/Simon Davis


Vaccination requires a complex system of people, supplies, facilities, equipment, policies, and processes. As a result, it can be challenging for decision-makers to understand the different costs incurred in the process of vaccination, as well as the multitude of health and economic benefits that can result from vaccination. Without a systems approach to understanding these costs, it can be difficult to see the secondary, tertiary, and other indirect effects of vaccination and make the best decisions on how to use constrained resources.

By using a systems approach, decision makers can better understand the potential indirect effects and implications of interventions and policies before implementing them in the real world.

To help policymakers, health officials, logisticians, managers of national immunisation programs, and others making decisions about vaccination see the whole picture of the processes and costs involved in vaccination, researchers from Public Health Informatics, Computational and Operations Research (PHICOR), the Centers for Disease Control and Prevention (CDC), and the University of North Carolina developed a systems map of the steps involved in an individual getting vaccinated, the associated vaccination program costs at service delivery level, and the health and economic impacts of vaccination.

Vaccinating hard-to-reach communities

To be able to identify the potential costs and benefits of vaccinating hard-to-reach communities, decision makers must first be able to understand the complex process of getting vaccines to people and how disruptions in each of these processes can make people hard to reach.

The need for systems approaches and tools

Computational simulation modelling and systems mapping are systematic ways that can be used to identify all the potential costs and benefits of vaccination and how they are connected. By using a systems approach, decision makers can better understand the potential indirect effects and implications of interventions and policies before implementing them in the real world, saving valuable time, effort, money, and other resources. The systems map was published in Vaccine and highlights each of the ways disruptions to the vaccination process can make people hard-to-reach.

For example, the systems map can help decision makers:

  • Identify each of the critical steps required for an individual to get vaccinated and understand how each are connected. This can help ensure that certain processes required for vaccination (e.g. ensuring individuals can travel to a vaccination site) are not overlooked during program planning. 
  • Determine where vaccination processes may be interrupted or weak and result in making communities hard to reach. Knowing which processes can be disrupted and lead to communities becoming hard to reach is important for overcoming these barriers and achieving higher vaccine coverage levels. 
  • Conduct a comprehensive economic evaluation of a country’s immunization program and identify where additional economic data may be needed. Often, traditional economic evaluations may not capture the full range of costs and benefits associated with vaccination, which can impact decisions about how best to fund a vaccination programme. 
  • Inform targetted interventions and policies to increase vaccination coverage for hard-to-reach communities. By understanding how communities can be hard to reach and where the costs and benefits may be different for these communities is critical to planning vaccination programmes. 

Cox SN, Wedlock PT, Pallas SW, Mitgang EA, Yemeke TT, Bartsch SM, Abimbola T, Sigemund SS, Wallace A, Ozawa S, Lee BY. A systems map of the economic considerations for vaccination: Application to hard-to-reach populations. Vaccine. 2021 May 24:S0264-410X(21)00605-8. doi: 10.1016/j.vaccine.2021.05.033. Epub ahead of print. PMID: 34045101.

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