Mise en place d’un système de surveillance syndromique national

The Problem : The detection of any expected or unexpected event in near real time.

Infectious diseases are one of the leading causes of mortality and morbidity in sub-Saharan Africa, and one of the major impediments to achieving the global health agenda (WHO, 2010a). They account for 20% of deaths in all age groups and 50% of infant mortality. Of the infectious diseases prevalent in sub-Saharan Africa, HIV/AIDS, tuberculosis and malaria are the major ones. Their prevalence is the highest. Other infectious diseases, such as respiratory infections, diarrhoeal diseases and neonatal infections, increase overall mortality and are particularly prevalent in children under 5 years of age. Filariasis and intestinal parasitosis will, in turn, increase general morbidity among populations. Life expectancy is low, with less than one in five living until the age of 70, while in high-income countries over two-thirds of the population lives beyond this age. Health systems that are often young and unstructured, with few human, material and financial resources, are struggling to cope with this health issue. These problems are compounded by regular epidemics, some of which have a high fatality rate.
The eradication of infectious diseases in Africa regularly collides with the continent’s challenges. Policies to control these diseases have been implemented with technical support from the WHO, through the establishment of specific programmes by States. HIV/AIDS, malaria and tuberculosis are receiving an additional dedicated funding effort as part of the “Global Fund” or other initiatives such as the “Millennium Development Goals”. However, to ensure monitoring and evaluation of endemic disease control programmes, a good knowledge of their frequency, distribution and risk factors is needed. However, this data is not always available in the majority of African countries. It is often obtained from isolated and incomplete epidemiological surveys, which do not reflect the reality of the extent of the health problem. Malaria is one of the priority diseases. Studies have shown that Gabon is a country of malaria hyperendemicity with perennial transmission (Richard-Lenoble et al., 1987, Wildling et al., 1995, Merlin et al., 1990, Maghendji-Ndzondo et al., 2016). The decline of more than 50% of confirmed cases, admissions or deaths related to malaria has been noted in several African countries (D’Acremont et al., 2010, Okiro et al., 2007). In Gabon, a study showed a decrease in the incidence of malaria from 45% in 2000 to 15% in 2008 in Libreville (Bouyou-Akotet et al., 2009).
System currently used: in Gabon, the surveillance system used is Integrated Disease Surveillance and Response (IDSR). The overall objective of the IDSR is to provide timely and sound bases for decision-making and the selection of public health interventions for effective control of communicable diseases. This system has several limitations: Gabon has a disease surveillance network with functional epidemic potential, integrating health departments and regions. Viral haemorrhagic fevers, chikungunya and dengue are now notifiable diseases. Monitoring data is coordinated centrally for analysis and actions. Samples from suspected cases are forwarded to the CIRMF, which acts as a reference laboratory. Nevertheless, using the IDSR, it is estimated that more than half of the available data is not collected, and that more than half of the potentially collected data is not transmitted centrally, thus explaining the slow responsiveness of this system.
It is therefore a question of proposing a more efficient alternative, that is easy to implement and less expensive. Syndromic surveillance thus consists of collecting or monitoring epidemiological indicators in real time, in order to detect (un)usual events earlier than in the previous system. This surveillance involves the use of tools for the production, transmission, management and sharing of digitised information for the benefit of medical and medico-social practices. Currently, there is no syndromic surveillance network and national epidemiological data exchange that could develop through an interconnection of existing networks in order to set up a syndromic watch.

The initiative is to implement this system using new information and communication technologies (ICT). Specific objectives: strengthen prevention and promote predictive medicine; analyse the impact of the current variability of infectious diseases with epidemic potential; develop new surveillance strategies (in e-health); propose the creation of a national syndromic surveillance database; propose an improvement of the epidemiological surveillance through interconnection of existing devices. Thanks to new information and communication technologies (NICT), the proposed solution allows the transmission of epidemiological data collected in near real time as an alternative to the standard surveillance system.