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Background: Human African trypanosomiasis (HAT) is a neglected tropical disease targeted for elimination ‘as a public health problem’ by 2020. The indicators to monitor progress towards the target are based on the number of reported cases, the related areas and populations exposed at various levels of risk, and the coverage of surveillance activities. Based on data provided by the National Sleeping Sickness Control Programmes (NSSCP), Non-Governmental Organizations (NGOs) and research institutions—and assembled in the Atlas of HAT—the World Health Organization (WHO) provides here an update to 2016 for these indicators, as well as an analysis of the epidemiological situation. Results: Trends for the two primary indicators of elimination are on track for the 2020 goal: 2,164 cases of HAT were reported in 2016 (as compared to the milestone of 4,000 cases), and for the period 2012–2016 280,000 km2 are estimated to be at moderate risk or higher (i.e. ≥ 1 case/10,000 people/year), as compared to the milestone of 230,000 km2. These figures correspond to reductions of 92% and 61% as compared to the respective baselines (i.e. 26,550 HAT cases in the year 2000, and 709,000 km2 exposed at various levels of risk for the period 2000–2004). Among the secondary indicators, an overall improvement in the coverage of at risk populations by surveillance activities was observed. Regarding passive surveillance, the number of fixed health facilities providing gambiense HAT diagnosis or treatment expanded, with 1,338 enumerated in endemic countries in 2017 (+52% as compared to the survey completed only sixteen months earlier). Concerning rhodesiense HAT, 124 health facilities currently provide diagnosis or treatment. The broadening of passive surveillance is occurring in a context of fairly stable intensity of active case finding, with between 1.8 million and 2.4 million people screened per year over the period 2012–2016. Discussion: Elimination of HAT as a public health problem by 2020 seems within reach, as the epidemiological trends observed in previous years are confirmed in this latest 2016 monitoring update. However, looking beyond 2020, and in particular to the 2030 goal of elimination of transmission as zero cases for the gambiense form of the disease only, there is no room for complacency. Challenges still abound, including ensuring the effective integration of HAT control activities in the health system, sustaining the commitment of donors and HAT endemic countries, and clarifying the extent of the threat posed by cryptic reservoirs (e.g. human asymptomatic carriers and the possible animal reservoirs in gambiense HAT epidemiology). WHO provides through the network for HAT elimination the essential coordination of the wide range of stakeholders to ensure synergy of efforts. [ABSTRACT FROM AUTHOR]

Background: Over the last few years, momentum has gathered around the feasibility and opportunity of eliminating gambiense human African trypanosomiasis (g-HAT). Under the leadership of the World Health Organization (WHO), a large coalition of stakeholders is now committed to achieving this goal. A roadmap has been laid out, and indicators and milestones have been defined to monitor the progress of the elimination of g-HAT as a public health problem by 2020. Subsequently, a more ambitious objective was set for 2030: to stop disease transmission. This paper provides a situational update to 2012 for a number of indicators of elimination: number of cases annually reported, geographic distribution of the disease and areas and populations at different levels of risk. Results: Comparing the 5-year periods 2003-2007 and 2008-2012, the area at high or very high risk of g-HAT shrank by 60%, while the area at moderate risk decreased by 22%. These are the areas where g-HAT is still to be considered a public health problem (i.e. > 1 HAT reported case per 10,000 people per annum). This contraction of at-risk areas corresponds to a reduction of 57% for the population at high or very high risk (from 4.1 to 1.8 million), and 20% for moderate risk (from 14.0 to 11.3 million). Discussion: Improved data completeness and accuracy of the Atlas of HAT enhanced our capacity to monitor the progress towards the elimination of g-HAT. The trends in the selected indicators suggest that, in recent years, progress has been steady and in line with the elimination goal laid out in the WHO roadmap on neglected tropical diseases. [ABSTRACT FROM AUTHOR]

Background: Human African trypanosomiasis (HAT), also known as sleeping sickness, persists as a public health problem in several sub-Saharan countries. Evidence-based, spatially explicit estimates of population at risk are needed to inform planning and implementation of field interventions, monitor disease trends, raise awareness and support advocacy. Comprehensive, geo-referenced epidemiological records from HAT-affected countries were combined with human population layers to map five categories of risk, ranging from ''very high'' to ''very low,'' and to estimate the corresponding at-risk population. Results: Approximately 70 million people distributed over a surface of 1.55 million km2 are estimated to be at different levels of risk of contracting HAT. Trypanosoma brucei gambiense accounts for 82.2% of the population at risk, the remaining 17.8% being at risk of infection from T. b. rhodesiense. Twenty-one million people live in areas classified as moderate to very high risk, where more than 1 HAT case per 10,000 inhabitants per annum is reported. Discussion: Updated estimates of the population at risk of sleeping sickness were made, based on quantitative information on the reported cases and the geographic distribution of human population. Due to substantial methodological differences, it is not possible to make direct comparisons with previous figures for at-risk population. By contrast, it will be possible to explore trends in the future. The presented maps of different HAT risk levels will help to develop site-specific strategies for control and surveillance, and to monitor progress achieved by ongoing efforts aimed at the elimination of sleeping sickness. [ABSTRACT FROM AUTHOR]

In this article, the authors discuss the programme of the World Health Organization (WHO) for the prevention of human African trypanosomiasis (HAT) known as sleeping sickness. They note that 24 countries, including Kenya, Liberia and Nigeria, have received support from WHO to examine their epidemiological status of HAT or to establish control and surveillance activities. They add that the number of cases reported has declined below 10,000 as the result of control and surveillance activities.