Measuring the impact of seasonal malaria chemoprevention as part of routine malaria control in Kita, Mali

Abstract

BackgroundSeasonal malaria chemoprevention (SMC) is a new strategy recommended by WHO in areas of highly seasonal transmission in March 2012. Although randomized controlled trials (RCTs) have shown SMC to be highly effective, evidence and experience from routine implementation of SMC are limited.MethodsA non-randomized pragmatic trial with pre-post design was used, with one intervention district (Kita), where four rounds of SMC with sulfadoxine + amodiaquine (SP + AQ) took place in August–November 2014, and one comparison district (Bafoulabe). The primary aims were to evaluate SMC coverage and reductions in prevalence of malaria and anaemia when SMC is delivered through routine programmes using existing community health workers. Children aged 3–59 months from 15 selected localities per district, sampled with probability proportional to size, were surveyed and blood samples collected for malaria blood smears, haemoglobin (Hb) measurement, and molecular markers of drug resistance in two cross-sectional surveys, one before SMC (July 2014) and one after SMC (December 2014). Difference-in-differences regression models were used to assess and compare changes in malaria and anaemia in the intervention and comparison districts. Adherence and tolerability of SMC were assessed by cross-sectional surveys 4–7 days after each SMC round. Coverage of SMC was assessed in the post-SMC survey.ResultsDuring round 1, 84% of targeted children received at least the first SMC dose, but coverage declined to 67% by round 4. Across the four treatment rounds, 54% of children received four complete SMC courses. Prevalence of parasitaemia was similar in intervention and comparison districts prior to SMC (23.4 vs 29.5%, p = 0.34) as was the prevalence of malaria illness (2.4 vs 1.9%, p = 0.75). After SMC, parasitaemia prevalence fell to 18% in the intervention district and increased to 46% in the comparison district [difference-in-differences (DD) OR = 0.35; 95% CI 0.20–0.60]. Prevalence of malaria illness fell to a greater degree in the intervention district versus the comparison district (DD OR = 0.20; 95% CI 0.04–0.94) and the same for moderate anaemia (Hb < 8 g/dL) (DD OR = 0.26, 95% CI 0.11–0.65). The frequency of the quintuple mutation (dhfr N51I, C59R and S108N + dhps A437G and K540E) remained low (5%) before and after intervention in both districts.ConclusionsRoutine implementation of SMC in Mali substantially reduced malaria and anaemia, with reductions of similar magnitude to those seen in previous RCTs. Improving coverage could further strengthen SMC impact. Trial registration clinical trial registration number NCT02894294

Impact of seasonal malaria chemoprevention on hospital admissions and mortality in children under 5 years of age in Ouelessebougou, Mali

“…This 39% reductions in all cause hospital admissions is consistent with the 41% of all-cause hospital admissions by Wilson et al in a meta analysis of the efficacy trials [3]. In the district of Kita, Mali a higher reduction 72% in number of severe malaria reported in the health centres in under 5 years of age, during the 2014 transmission season when SMC was implemented compared the 2013 season when SMC was not implemented [7]. For severe malaria hospitalizations, the study found a relative risk IRR of 0.53 (95% CI 0.36-0.79) corresponding to a 47% reduction of malaria-related hospitalizations in the intervention area.…”

Effect of routine seasonal malaria chemoprevention on malaria trends in children under 5 years in Dangassa, Mali

“…An improvement of haemoglobin level (Table 1) was observed over the intervention period (September to November). The above observations could be attributed to SMC as it has been shown in many other studies about the protective effect of SMC on malaria in children in Africa [12][13][14]. The regular monthly administration of SP + AQ allows maintenance of drug concentration in blood and prevents parasite growth and avoids red blood cell destruction, which in turn prevents haemoglobin level decrease by malaria parasites [14,15].…”

Adherence and Population Pharmacokinetic Properties of Amodiaquine When Used for Seasonal Malaria Chemoprevention in African Children

“…To date, a number of direct and indirect methods have been developed to investigate medication adherence for either treatment of malaria or SMC. Self‐report, pill counts, or a combination of both are most feasible, relatively low cost, and shown to be the most useful indirect methods to estimate adherence in malaria therapy and SMC . However, the response bias of self‐report (and to a lesser degree, recall bias) by patients may result in an overestimation of adherence .…”