Transient malaria suppression after mass drug administration with artemisinin-piperaquine in a holoendemic, non-isolated region of Togo

Background Mass drug administration (MDA) as a malaria control strategy in holoendemic, non-isolated regions of continental Africa lacks robust evidence regarding its ability to sustain malaria reduction. We evaluated the effect of artemisinin-piperaquine (AP) MDA in Togo. Methods In a quasi-experimental study, three monthly AP MDA rounds (Mar-May 2017) were delivered to ~ 160,000 residents across 198 villages in Est-Mono prefecture (intervention zone). Outcomes were compared to ~ 146,000 residents across 182 villages in Anié prefecture (control zone), which receiving standard national malaria control programme (NMCP) without MDA. Parasite and gametocyte carriage in children aged 6–60 months was assessed microscopically at baseline, 2 months, and 5 months post-MDA, and health facility data on malaria (2016–2018) were analyzed. Results 94–96% coverage of AP MDA in intervention zone. AP was well-tolerated, with primarily mild gastrointestinal adverse events. Two months post-MDA, the prevalence of malaria parasitemia in Est-Mono children decreased significantly from 82.1% to 37.7% ( P  < 0.0001), contrasting with a minimal reduction (83.0% to 76.0%, P  < 0.0001) in Anié. However, gametocytemia remained high and unchanged in Est-Mono (6.1% pre-MDA vs. 6.9% post-MDA, P  = 0.499) compared to an increase in Anié (7.2% to 10.6%, P  = 0.005). Five months post-MDA, the prevalence of malaria parasitemia in Est-Mono rebounded to 72.6% (vs. 82.0% in Anié). Outpatient malaria cases in Est-Mono health facilities during the MDA period (March-June 2017) decreased by 73.5% compared to the same period in 2016, but returned to pre-intervention levels by 2018. Conclusions AP-MDA led to a rapid but transient reduction in malaria prevalence in this holoendemic, non-isolated setting. However, sustained malaria control requires integrating MDA with complementary strategies. Trial registration: The study protocol was approved by the Togolese Committee of Bioethics on Health Research (N°0001/2016/CBRS) on 7 January 2016 and by the Ethics Committee of Guangdong Provincial Hospital of Chinese Medicine (B2017-054-01) on 27 March 2017.