The elimination of human African trypanosomiasis: Achievements in relation to WHO road map targets for 2020

Abstract

Background In the 20th century, epidemics of human African trypanosomiasis (HAT) ravaged communities in a number of African countries. The latest surge in disease transmission was recorded in the late 1990s, with more than 35,000 cases reported annually in 1997 and 1998. In 2013, after more than a decade of sustained control efforts and steady progress, the World Health Assembly resolved to target the elimination of HAT as a public health problem by 2020. We report here on recent progress towards this goal. Methodology/principal findings With 992 and 663 cases reported in 2019 and 2020 respectively, the first global target was amply achieved (i.e. fewer than 2,000 HAT cases/year). Areas at moderate or higher risk of HAT, where more than 1 case/10,000 people/year are reported, shrunk to 120,000 km2 for the five-year period 2016–2020. This reduction of 83% from the 2000–2004 baseline (i.e. 709,000 km2) is slightly below the target (i.e. 90% reduction). As a result, the second global target for HAT elimination as a public health problem cannot be considered fully achieved yet. The number of health facilities able to diagnose and treat HAT expanded (+9.6% compared to a 2019 survey), thus reinforcing the capacity for passive detection and improving epidemiological knowledge of the disease. Active surveillance for gambiense HAT was sustained. In particular, 2.8 million people were actively screened in 2019 and 1.6 million in 2020, the decrease in 2020 being mainly caused by COVID-19-related restrictions. Togo and Côte d’Ivoire were the first countries to be validated for achieving elimination of HAT as a public health problem at the national level; applications from three additional countries are under review by the World Health Organization (WHO). Conclusions/significance The steady progress towards the elimination of HAT is a testament to the power of multi-stakeholder commitment and coordination. At the end of 2020, the World Health Assembly endorsed a new road map for 2021–2030 that set new bold targets for neglected tropical diseases. While rhodesiense HAT remains among the diseases targeted for elimination as a public health problem, gambiense HAT is targeted for elimination of transmission. The goal for gambiense HAT is expected to be particularly arduous, as it might be hindered by cryptic reservoirs and a number of other challenges (e.g. further integration of HAT surveillance and control into national health systems, availability of skilled health care workers, development of more effective and adapted tools, and funding for and coordination of elimination efforts).

Scaling up of tsetse control to eliminate Gambian sleeping sickness in northern Uganda

“…Sleeping sickness (human African trypanosomiasis, HAT) is caused by sub-species of Trypanosoma brucei spread by tsetse flies ( Glossina ). In the 20 th Century there were three major epidemics of HAT, the most recent being in the late 1990s when up to >35000 cases were reported annually [ 1 ]. WHO declared the aim of eliminating HAT as a public health problem by 2020 and the complete interruption of transmission by 2030.…”

“…Sub-species of Glossina fuscipes are the major vectors across a large swathe of Central Africa, extending across South Sudan, Uganda, the Democratic Republic of Congo (DRC), Central African Republic (CAR) and Chad [ 2 ]. Together, these countries contributed >90% (27296/32275) of all cases of gHAT reported globally in the period 2011–2020 [ 1 ].…”

Enhancing research integration to improve One Health actions: learning lessons from neglected tropical diseases experiences

“…In these contexts, alternative or additional strategies developed in Southern Mexico and Central America, based on an eco-bio-social approach and participatory research, have shown promising outcomes 12. The successful results obtained against lymphatic filariases13 14 and human African trypanosomiasis15 16 were also due, at least in part, to the use of multiple strategies, based on the integration of research outputs for improving medical surveillance and vector control (with insecticide-treated bed nets and insecticide impregnated screens, respectively) with an important component of participatory research.…”

Spatial Distribution of Tsetse Flies and Trypanosome Infection Status in a Vector Genetic Transition Zone in Northern Uganda

“…The diseases impose a severe burden on human and livestock health in sub-Saharan Africa [ 1 ]. Thirty-seven countries are affected, with more than 50 million cattle, 70 million small ruminants [ 2 ], and 55 million people at risk of contracting the diseases [ 3 ]. The Food and Agricultural Organization (FAO) of the United Nations estimates that Africa loses up to US$1.5 billion annually as a result of the disease [ 4 ].…”