Abstract
BackgroundTreatment of clinical Plasmodium falciparum malaria with sulfadoxine-pyrimethamine (SP) and amodiaquine (AQ) is associated with increased post-treatment gametocyte carriage. The effect of seasonal malaria chemoprevention (SMC) with SP and AQ on gametocyte carriage was assessed in asymptomatic P. falciparum infected children.MethodsThe study was carried out in eastern Gambia. Asymptomatic P. falciparum malaria infected children aged 24–59 months old who were eligible to receive SMC (SMC group) and children 5–8 years that were not eligible to receive SMC (comparison group) were recruited. Gametocytaemia was determined by molecular methods before and after SMC administration. Gametocyte carriage between the groups was compared using the chi-squared test and within-person using conditional logistic regression.ResultsDuring the 2017 and 2018 malaria transmission seasons, 65 and 75 children were recruited in the SMC and comparison groups, respectively. Before SMC administration, gametocyte prevalence was 10.7% (7/65) in the SMC group and 13.3% (10/75) in the comparison group (p = 0.64). At day 13 (IQR 12, 13) after SMC administration, this was 9.4% (5/53) in children who received at least the first dose of SMC treatment and 12.7% (9/71) for those in the comparison group (p = 0.57). Similarly, there was no difference in prevalence of gametocytes between children that adhered to all 3-day doses of SMC treatment 15.6% (5/32) and those in the comparison group (p = 0.68). In the SMC group, within-group gametocyte carriage was similar before and after SMC administration in children that received at least the first dose of SMC treatment (OR 0.6, 95% CI 0.14–2.51; p = 0.48) and in those that adhered to all 3-day doses of SMC treatment (OR 1.0, 95% CI 0.20–4.95; p = 1.0).ConclusionIn this study with relative low gametocyte prevalence prior to SMC treatment, no evidence was observed that SMC treatment increased gametocyte carriage in asymptomatic P. falciparum malaria infected children.
Highlights
Treatment of clinical Plasmodium falciparum malaria with sulfadoxine-pyrimethamine (SP) and amodi‐ aquine (AQ) is associated with increased post-treatment gametocyte carriage
Gametocyte prevalence in children that received at least the first dose of seasonal malaria chemo‐ prevention (SMC) treatment (SP plus AQ) and in those that adhered to all 3-day doses of SMC treatment (SP plus AQ on day 1 and AQ alone on days 2 and 3) was each compared with gametocyte prevalence in the comparison group
At 13 days post-treatment, there was no difference in gametocyte prevalence between children in the SMC group who received at least the first dose of SMC treatment (SP and AQ) (9.4%, 5/53) and those in the comparison group (12.7%, 9/71), (p = 0.57)
Summary
Treatment of clinical Plasmodium falciparum malaria with sulfadoxine-pyrimethamine (SP) and amodi‐ aquine (AQ) is associated with increased post-treatment gametocyte carriage. Treatment of symptomatic patients with SP, AQ, chloroquine (CQ), and piperaquine (PQ) is associated with increased gametocyte carriage and or density [9,10,11,12,13,14] Mechanisms such as enhancement of gametocyte production in response to drug-induced stress, release of sequestered gametocytes and up-regulation of gametocyte production in response to subcurative dosage are current hypotheses for the emergence of post-treatment gametocytes [14, 15], that can be infectious to the vector [12,13,14, 16]. The transmission potential of post-treatment gametocytes has been known for about 100 years [17], it has only recently drawn attention in relation to the current drive towards malaria elimination and eradication and the increased knowledge on the differential impact of anti-malarials on gametocyte persistence and infectivity [18]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
