BackgroundThe widespread use of insecticide-treated nets (LLINs) leads to the development of vector resistance to insecticide. This resistance can reduce the effectiveness of LLIN-based interventions and perhaps reverse progress in reducing malaria morbidity. To prevent such difficulty, it is important to know the real impact of resistance in the effectiveness of mosquito nets. Therefore, an assessment of LLIN efficacy was conducted in malaria prevention among children in high and low resistance areas.MethodsThe study was conducted in four rural districts and included 32 villages categorized as low or high resistance areas in Plateau Department, south-western Benin. Larvae collection was conducted to measure vector susceptibility to deltamethrin and knockdown resistance (kdr) frequency. In each resistance area, around 500 children were selected to measure the prevalence of malaria infection as well as the prevalence of anaemia associated with the use of LLINs.ResultsObserved mortalities of Anopheles gambiae s.s population exposed to deltamethrin ranged from 19 to 96%. Knockdown resistance frequency was between 38 and 84%. The prevalence of malaria infection in children under five years was 22.4% (19.9-25.1). This prevalence was 17.3% (14.2-20.9) in areas of high resistance and 27.1% (23.5-31.1) in areas of low resistance (p = 0.04). Eight on ten children that were aged six - 30 months against seven on ten of those aged 31–59 months were anaemic. The anaemia observed in the six to 30-month old children was significantly higher than in the 31–59 month old children (p = 0.00) but no difference associated with resistance areas was observed (p = 0.35). The net use rate was 71%. The risk of having malaria was significantly reduced (p < 0.05) with LLIN use in both low and high resistance areas. The preventive effect of LLINs in high resistance areas was 60% (95% CI: 40–70), and was significantly higher than that observed in low resistance areas (p < 0.05).ConclusionThe results of this study showed that the resistance of malaria vectors seems to date not have affected the impact of LLINs and the use of LLINs was highly associated with reduced malaria prevalence irrespective of resistance.

BackgroundInsecticide-based interventions have averted more than 500 million malaria cases since 2000, but insecticide resistance in mosquitoes could bring about a rebound in disease and mortality. This study investigated whether insecticide resistance was associated with increased incidence of clinical malaria.MethodsIn an area of southern Benin with insecticide resistance and high use of insecticide-treated nets (ITNs), malaria morbidity and insecticide resistance were measured simultaneously in 30 clusters (villages or collections of villages) multiple times over the course of 2 years. Insecticide resistance frequencies were measured using the standard World Health Organization bioassay test. Malaria morbidity was measured by cases recorded at health facilities both in the whole population using routinely collected data and in a passively followed cohort of children under 5 years old.ResultsThere was no evidence that incidence of malaria from routinely collected data was higher in clusters with resistance frequencies above the median, either in children aged under 5 (RR = 1.27 (95% CI 0.81–2.00) p = 0.276) or in individuals aged 5 or over (RR = 1.74 (95% CI 0.91–3.34) p = 0.093). There was also no evidence that incidence was higher in clusters with resistance frequencies above the median in the passively followed cohort (RR = 1.11 (0.52–2.35) p = 0.777).ConclusionsThis study found no association between frequency of resistance and incidence of clinical malaria in an area where ITNs are the principal form of vector control. This may be because, as other studies have shown, ITNs continue to offer some protection from malaria even in the presence of insecticide resistance. Irrespective of resistance, nets provide only partial protection so the development of improved or supplementary vector control tools is required to reduce Africa’s unacceptably high malaria burden.

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Long-lasting insecticidal nets (LLINs) have proved to be an important tool for the malaria control and other vector-borne diseases. Benin, by its National Malaria Control Program, conducted in July, 2011 a universal distribution campaign where approximately 5 million of nets were distributed. But after this mass-distribution, questions arise: Do people effectively use or not use the mosquito nets freely distributed? To clarify these questions, this study was conducted on LLINs coverage, use and physical condition in Benin one year after their distribution. The households were randomly selected from 32 clusters. Data on bed net ownership and usage, physical condition of the nets, other characters and issues related to sourcing were asked of all targets to assess the origins of LLIN found at the household level. Of the total surveyed, 88.96% had at least one LLIN. 87.19% of these nets come from the last campaign, 9.1% were from pregnant women voucher clinic delivery systems and 3.20% were purchased full price. 84% of the nets were reportedly used the night preceding the survey. Around 89% of the total of LLINs observed was in good condition. The universal distribution campaign in Benin has significantly increased LLIN coverage and ownership policy in the community.

Given the valuable health, development, and economic benefits of human milk exclusive breastfeeding (EBF) is recommended by the World Health Organisation for the first six months of an infant’s life. Many resource-limited regions in Africa do not line-up with these recommendations therefore EBF promotion efforts on the continent need to be scaled up and monitored. This study explores the human milk intake volumes of 5 countries (Benin, Central African Republic, Morocco, South Africa and Tanzania) both at country level and in a pooled sample at 3 months (n= 355) and at 6 months (n=193). Mean human milk intake volumes in the pooled samples were 697.6 g/day at 3 months and 714.9 g/day at 6 months. EBF was determined both by maternal recall as well as using the deuterium oxide dose-to-mother technique using two different cut-offs of non-milk oral intake. Comparison of these results showed substantial over-reporting of EBF by maternal recall, which suggests that actual rates of EBF are even lower than reported thus highlighting the importance of scaling-up EBF promotion strategies.