Tracking and eliminating disease with smartphones

Young child having their height measured
Photo credit: Javier Acebal, Sightsavers
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by Sightsavers
5 January 2020

Love them or loathe them - smartphones have become indispensable in the modern age and many of us would panic if we left the house without one. For those living in countries where blinding trachoma is endemic their role is even more vital - they help save sight.

A pioneering project called Tropical Data uses mobile phone technology to conduct surveys about the infectious eye disease all over the world, even in conflict-stricken countries like Yemen. Trachoma is a painful but preventable eye infection that begins a bit like conjunctivitis but can cause blindness if left untreated. A global partnership of governments, communities and international organisations (including Sightsavers) are working to eliminate the disease around the world. With the help of Tropical Data, we hope to achieve this in the countries we work by 2025.

The project is run by a consortium of organisations who work with health organisations to gather and interpret data which shows how we can eliminate trachoma as a public health problem in each area. We need to know how many people are infected, and where they are, in order to treat them. We also need numbers to know when a disease is eliminated, and no longer a public health problem.

We want a world where no-one goes blind from avoidable causes, and where everyone can participate equally in society.

An innovative approach

Tropical Data took over from the Global Trachoma Mapping Project (GTMP) which in 2012 became, the largest ever infectious disease survey ever carried out. There were 2.6 million people examined across 29 countries – which works out as one person every 40 seconds.

Both projects use smartphones to gather information about trachoma, with teams going door to door in remote communities to examine residents and record what they see. So far 7.7 million people have been examined in nearly eight years across 49 countries this way and in 2020 the project is expected to start work in its 50th country.

The challenges of conflict zones

For the survey and the data to be accurate and usable it is essential that the data collection is consistent everywhere, but this can be particularly challenging when it comes to conflict zones such as Yemen, where war has thrown the country’s infrastructure and health systems into chaos since 2015. Despite the challenges, work in Yemen is crucial, where it is thought that that 2.5 million people are at risk of contracting trachoma. The lessons learned from operating in such difficult conditions could help us to eliminate the infection as a public health issue around the world.

Sightsavers team member checking a childs eyes
Image from Sightsavers

The global fight against neglected tropical disease

This innovative approach has proven key for worldwide efforts to tackle neglected diseases. Alongside data gathering, we are training health workers in endemic countries which will strengthen local health systems in the long term. These health workers are given rigorous training as it is vital everyone works to the same standard in every country, for the results to be consistent. 

The evidence generated by the Tropical Data project will help  ministries of health pinpoint exactly where to run trachoma treatment programmes and offer life-changing support. It also highlights where treatment programmes are no longer needed because interventions have been a success. Crucially, this helps countries gather evidence for the World Health Organization (WHO) to show where they are free from the disease, so trachoma elimination can be declared. Tropical Data is run by a consortium of partners including the International Trachoma Initiative (ITI), the London School of Hygiene and Tropical Medicine, RTI International and Sightsavers. 

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