Grantee: Ona (True Cover)

Tracking the true immunization coverage in communities through satellite imagery

Matt Berg, CEO, Ona
A child is carried by its mother attending a clinic held by a community nurse where basic health care services, including growth monitoring and immunizations, are provided to infants and children in the Chibolele area, Ndola, Copperbelt Province, Zambia
17 July 2019

Bill & Melinda Gates Foundation and UNICEF are joining forces  by accelerating Innovation for strengthening Vaccination Systems -- starting with better collection and use of critical data. UNICEF’s Innovation Fund is supporting eight grant recipients of the Gates Foundation’s Grand Challenges Explorations Round 22 with its cutting edge piloting and scaling methodologies and tools. Read more from Grant Recipient True Cover, below.



Target population estimates for immunization are typically derived from government census or large-scale statistical surveys. Data is centrally maintained, immediately obsolete, costly and results in estimates unrepresentative of the true population of children within a catchment area. This often leads to inflated and inaccurate immunization coverage estimates. There should be a better, smarter way to gather immunization data and coverage estimates.

True Cover being used

Our solution is to identify all potential livable structures in a community using high-resolution satellite imagery and community mapping.  From here, we’ll use our tasking algorithms to automatically generate a random sample of structures to be visited by community surveillance teams. 

These teams will identify under-five children in the household and use our digital tool to record immunization status. This captured data will feed into modeling software that will help us predict a “true” immunization coverage rate specific to the local community. The system will also help guide health workers to which homes they should visit next to improve the coverage estimate.  The “true coverage” rates can be visualized on a "living" map, allowing health workers to identify and target under-vaccinated populations within their communities for targeted outreach services.

“Our goal is to help health workers at the community level understand where are the places in their community where children are not accessing the services they deserve.  We hope this empowers health workers to find these children so they can benefit from the protections immunizations provide.”

A nurse (right) administers a pentavalent vaccine to an infant during a clinic to immunize babies and young children at the Chipata Clinic, Lusaka, Zambia

A Closer Look

The inspiration came from our work supporting the MoH in implementing a national Electronic Immunization Registry (EIR) in Zambia as part of the Better Immunization Data (BID) initiative.  

Speaking to nurses, we realized they struggled to really know what the actual coverage rates were in their community.  They just relied on demographic estimates that showed them achieving very high (likely inflated) coverage rates.  

We felt if we could equip them to better understand coverage rates within their community they would be more empowered to take action to close the coverage gap.

We’ve spent the last 4 years working with a group called Akros to develop innovative approaches using geospatial targeting and tasking to help improve indoor residual spraying programs.  By doing this, we developed validated a lot of the foundational ideas used in our proposal. Namely, we can identify where all people live using high-resolution satellite imagery and then using innovative new mobile data collection tools task them to visit those locations to provide a service.  Since we now know how to do this we wanted to see if we could apply the same principals for coverage estimates.

Team Ona

Team & Diversity

We believe in a multidisciplinary approach.

Our team with diverse skills and backgrounds has built and validated a lot of important mobile data collection tools and techniques needed for this work. We also have partnered with some of the leading geospatial epidemiologists in the world to bring in decades of research and experience applying similar modeling approaches for Malaria risk prediction.  Lastly, and very important is that we work with great local implementing partners to help us test this work.

The Way Ahead

Our goal is to enable local communities to have better visibility of coverage rates for essential health services at the community level.  If we demonstrate success, we hope this approach will help compliment or even replace some aspects of the MICS and DHS survey.