The event, organized by the Mérieux Foundation in collaboration with the Bill & Melinda Gates Foundation, brought together researchers (members of the THSTI, IVI and NIH institutes1), along with representatives of international organizations, such as the World Health Organization and the NGO PATH.
The main goal of this conference was to define the Target Product Profile (TPP) for the diagnosis of typhoid fever. A TPP describes how a diagnostic tool will be used, along with its necessary characteristics. The emergence of typhoid conjugate vaccines, water sanitation and hygiene promotion, along with socio-economic progress, have reinforced the control of typhoid fever.
Disease incidence data on populations, however, are scarce and not sufficiently reliable owing to the lack of specificity and/or sensitivity in the reference diagnostic tests (blood culture and Widal-Felix test). Typhoid fever thus requires further targeted research and development to define appropriate diagnostic tools, and also to determine the resources and actions needed to control this major public health problem.
About enteric fevers
Enteric fevers are serious infectious diseases caused by the ingestion of water or food contaminated with Salmonella type bacteria by contact with human fecal matter. Without treatment, these diseases are associated with significant mortality and morbidity worldwide, particularly in the poor populations of developing countries with limited resources, where hygiene is precarious. The diseases are endemic in Southeast Asia and sub-Saharan Africa.
Mérieux Foundation actions in the field of enteric infections
Typhoid Diagnostics for Measuring Disease Burden
Numerous studies have highlighted a strong increase in cases of paratyphoid fever in some parts of the world, particularly in Asia and Africa. Since January 2012, the Mérieux Foundation Emerging Pathogens Laboratory has been developing a molecular method for the direct detection and identification of enteric fever pathogens (Salmonella typhi and Salmonella paratyphi A) from blood samples taken from suspected cases of typhoid. The test can be performed on lower volumes of blood, consistent with the quantities which can be taken from both children and adults.
This molecular method was validated on clinical samples in Bangladesh, thanks to funding from the Bill & Melinda Gates Foundation. In 2016, further funding from the Bill & Melinda Gates Foundation enabled the Mérieux Foundation to extend test evaluation to Africa (Burkina Faso, Ghana and Malawi), where enteric fever prevalence is not only high, but also of a different etiologic origin.
The Mérieux Foundation also hosts the Initiative against Diarrheal and Enteric diseases in Africa and Asia (IDEA). IDEA brings together a multidisciplinary, multinational and independent group of healthcare professionals involved in cholera control in Africa and Asia.
This initiative is based on field expertise federating national and international actions and creating multi-sector synergies by organizing workshops in Africa and Asia. The global aim of IDEA, supported by Valneva, bioMérieux and Sanofi Pasteur, is to contribute to the effective control, prevention and eradication of cholera, by helping countries develop national action plans.
1 Translational Health Science and Technology Institute (THSTI), International Vaccine Institute (IVI), National Institutes of Health (NIH).