Accelerating elimination of sleeping sickness from the Guinean littoral through enhanced screening in the post-Ebola context: A retrospective analysis

Abstract

Activities to control human African trypanosomiasis (HAT) in Guinea were severely hampered by the Ebola epidemic that hit this country between 2014 and 2016. Active screening was completely interrupted and passive screening could only be maintained in a few health facilities. At the end of the epidemic, medical interventions were progressively intensified to mitigate the risk of HAT resurgence and progress towards disease elimination. A retrospective analysis was performed to evaluate the medical activities that were implemented in the three most endemic prefectures of Guinea (Boffa, Dubreka and Forecariah) between January 2016 and December 2018. Passive screening using rapid diagnostic tests (RDTs) was progressively resumed in one hundred and one health facilities, and active screening was intensified by visiting individual households and performing RDTs, and by conducting mass screening in villages by mobile teams using the Card Agglutination Test for Trypanosomiasis. A total of 1885, 4897 and 8023 clinical suspects were tested in passive, while 5743, 14442 and 21093 people were actively screened in 2016, 2017 and 2018, respectively. The number of HAT cases that were diagnosed first went up from 107 in 2016 to 140 in 2017, then subsequently decreased to only 73 in 2018. A progressive decrease in disease prevalence was observed in the populations that were tested in active and in passive between 2016 and 2018. Intensified medical interventions in the post-Ebola context first resulted in an increase in the number of HAT cases, confirming the fear that the disease could resurge as a result of impaired control activities during the Ebola epidemic. On the other hand, the decrease in disease prevalence that was observed between 2016 and 2018 is encouraging, as it suggests that the current strategy combining enhanced diagnosis, treatment and vector control is appropriate to progress towards elimination of HAT in Guinea. Guinea has been consistently reporting the largest number of sleeping sickness cases in Western Africa since 2002. The Ebola epidemic that severely hit this country between 2014 and 2016 resulted in an interruption of most medical activities to control sleeping sickness, which was associated with an increase in the number of cases reported in 2016. In order to contain the resurgence of sleeping sickness and to bring it back on the path towards elimination, activities to screen and diagnose patients were intensified by strengthening the capacity of health facilities, and by visiting villages and households to test at-risk populations, while vector control was extended to cover all active foci in the country. This article presents the results that were obtained by the National Sleeping Sickness Control Program of Guinea after the Ebola epidemic by enhancing medical activities in the coastal region, where most cases of sleeping sickness are found. These efforts first resulted in an increase in the number of cases being diagnosed in 2016 and in 2017, and was then followed by an encouraging decline in 2018, thus raising hopes that the disease could be eliminated in the near future in Guinea.