Global disease mapping identifies 100 million people living at risk of blindness from trachoma

10 Feb 2016

A map showing GTMP mapped areasThe ground breaking three-year Global Trachoma Mapping Project (GTMP) involving many International Coalition for Trachoma Control (ICTC) members has revealed that 100 million people are at risk of blindness from trachoma. 

GTMP, launched in December 2012 and completed in January 2016, saw surveyors collect data on 2.6 million people in 29 countries using Android smartphones – examining a staggering one person every 40 seconds on average. 

During the last three years, more than 550 teams of trained surveyors including ophthalmic nurses and other government eye health care workers visited millions of people in the most remote locations of 29 countries, including Chad, Colombia, Eritrea, Pakistan, Papua New Guinea, Solomon Islands, Yemen as well as Ethiopia, a high burden country where over 50 million people are living in endemic areas. The sample surveyed represents a global population of 224 million people. 

In just three years, GTMP captured and shared data on the Trachoma Atlas database on more districts than had been ever previously been recorded. No data had previously existed on these areas due to issues including remoteness, insecurity, insufficient funding or competing public health priorities. 

By accurately pinpointing the world’s trachoma endemic areas, projects to tackle trachoma can be better planned and funding can be more effectively and efficiently channelled. The data is already playing an integral role in speeding up efforts to eliminate this ancient disease. Having a complete map of the disease’s prevalence means that ministries of health in endemic countries have the evidence base to focus health strategies to tackle this neglected tropical disease with WHO-approved interventions of surgery, antibiotics, face-cleanliness and environmental improvements. 

The project has also supported the strengthening of public health systems by training eye health workers in trachoma survey methodology; analysis and data management; and, providing support to publish the survey findings in peer reviewed journals.

Led by ICTC member Sightsavers, GTMP was a partnership of 30 ministries of health, the London School of Hygiene & Tropical Medicine, the World Health Organization, the International Trachoma Initiative and over 20 ICTC members. In total over 60* partners worked together across the world, representing a combined effort of an estimated 2,500 people globally. Virginia Sarah, ICTC’s Chair, welcomed the outcome of the project as great example of the benefits of collaboration:

"Together, we can overcome great hurdles and achieve the exceptional."

View the interactive feature which maps the world’s largest infectious cause of avoidable blindness.

*Partner organizations: AMREF, Barraqua Institue, BICO, Brien Holden Vision Institute, The Carter Center, College of Ophthalmology & Allied Vision Sciences, The Fred Hollows Foundation, FHI 360, Helen Keller International, International Trachoma Initiative (The Task Force for Global Health), Johns Hopkins University, Kilimanjaro Centre for Community Ophthalmology, Light for the World (Austria), Light for the World (Netherlands), London School of Hygiene & Tropical Medicine, Magrabi Foundation, Mitosath, ORBIS, Organisation for the Prevention of Blindness (OPC), Organizacion Panamericana de la Salud (PAHO), RTI International, Sightsavers and the World Health Organization. 

Ethiopian Regional Health Bureaus worked on specific projects in: Afar, Beneshangul Gumuz, Gambella, Oromia, Somali, Southern Nations Nationalities and Peoples’ Region and Tigray. 

Ministries of health including: Benin, Cambodia, Chad, Colombia, Cote d' Ivoire, Democratic Republic of Congo, Egypt, Eritrea, Ethiopia, Fiji, Guinea, Kiribati, Laos, Malawi, Mexico, Mozambique, Nigeria, Pakistan, Papua New Guinea, Yemen, Zanzibar and Zimbabwe. (In addition ministries of health in Cameroon and Nepal conducted baseline mapping projects during the life of GTMP without the use of GTMP methodology.) 

Funders: DFID and USAID.