Pharmacokinetics of mefloquine and its effect on sulfamethoxazole and trimethoprim steady-state blood levels in intermittent preventive treatment (IPTp) of pregnant HIV-infected women in Kenya.
ABSTRACT: Intermittent preventive treatment in pregnancy with sulfadoxine/pyrimethamine is contra-indicated in HIV-positive pregnant women receiving sulfamethoxazole/trimethoprim prophylaxis. Since mefloquine is being considered as a replacement for sulfadoxine/pyrimethamine in this vulnerable population, an investigation on the pharmacokinetic interactions of mefloquine, sulfamethoxazole and trimethoprim in pregnant, HIV-infected women was performed.A double-blinded, placebo-controlled study was conducted with 124 HIV-infected, pregnant women on a standard regimen of sulfamethoxazole/trimethoprim prophylaxis. Seventy-two subjects received three doses of mefloquine (15 mg/kg) at monthly intervals. Dried blood spots were collected from both placebo and mefloquine arms four to 672 h post-administration and on day 7 following a second monthly dose of mefloquine. A novel high-performance liquid chromatographic method was developed to simultaneously measure mefloquine, sulfamethoxazole and trimethoprim from each blood spot. Non-compartmental methods using a naïve-pooled data approach were used to determine mefloquine pharmacokinetic parameters.Sulfamethoxazole/trimethoprim prophylaxis did not noticeably influence mefloquine pharmacokinetics relative to reported values. The mefloquine half-life, observed clearance (CL/f), and area-under-the-curve (AUC0??) were 12.0 days, 0.035 l/h/kg and 431 µg-h/ml, respectively. Although trimethoprim steady-state levels were not significantly different between arms, sulfamethoxazole levels showed a significant 53% decrease after mefloquine administration relative to the placebo group and returning to pre-dose levels at 28 days.Although a transient decrease in sulfamethoxazole levels was observed, there was no change in hospital admissions due to secondary bacterial infections, implying that mefloquine may have provided antimicrobial protection.
Project description:Trimethoprim-sulfamethoxazole prophylaxis is recommended for HIV-exposed infants until breastfeeding ends and HIV infection has been excluded. Extending prophylaxis with a focus on preventing malaria may be beneficial in high transmission areas. We investigated three regimens for the prevention of malaria in young HIV-exposed children.An open-label, randomized controlled trial.Tororo, Uganda, a rural area with intense, year-round, malaria transmission.Two hundred infants aged 4-5 months enrolled and 186 randomized after cessation of breastfeeding and confirmed to be HIV uninfected (median 10 months of age).No chemoprevention, monthly sulfadoxine-pyrimethamine, daily trimethoprim-sulfamethoxazole or monthly dihydroartemisinin-piperaquine given from randomization to 24 months of age.The primary outcome was the incidence of malaria during the intervention period. Secondary outcomes included the incidence of hospitalization, diarrhoeal illness, or respiratory tract infection; prevalence of anaemia and asymptomatic parasitemia; measures of safety; and incidence of malaria over 1 year after the intervention was stopped.During the intervention, the incidence of malaria in the no chemoprevention group was 6.28 episodes per person-year at risk. Protective efficacy was 69% [95% confidence interval (95% CI) 53-80, P?<?0.001] for dihydroartemisinin-piperaquine, 49% (95% CI 23-66, P?=?0.001) for trimethoprim-sulfamethoxazole and 9% for sulfadoxine-pyrimethamine (95% CI -35 to 38, P?=?0.65). There were no significant differences in any secondary outcomes, with the exception of a lower prevalence of asymptomatic parasitemia in the dihydroartemisinin-piperaquine arm.Monthly chemoprevention with dihydroartemisinin-piperaquine was well tolerated and associated with a significant reduction in malaria in young HIV-exposed children.
Project description:OBJECTIVES:This study aimed to define the molecular basis of co-trimoxazole resistance in Malawian pneumococci under the dual selective pressure of widespread co-trimoxazole and sulfadoxine/pyrimethamine use. METHODS:We measured the trimethoprim and sulfamethoxazole MICs and analysed folA and folP nucleotide and translated amino acid sequences for 143 pneumococci isolated from carriage and invasive disease in Malawi (2002-08). RESULTS:Pneumococci were highly resistant to both trimethoprim and sulfamethoxazole (96%, 137/143). Sulfamethoxazole-resistant isolates showed a 3 or 6 bp insertion in the sulphonamide-binding site of folP. The trimethoprim-resistant isolates fell into three genotypic groups based on dihydrofolate reductase (encoded by folA) mutations: Ile-100-Leu (10%), the Ile-100-Leu substitution together with a residue 92 substitution (56%) and those with a novel uncharacterized resistance genotype (34%). The nucleotide sequence divergence and dN/dS of folA and folP remained stable from 2004 onwards. CONCLUSIONS:S. pneumoniae exhibit almost universal co-trimoxazole resistance in vitro and in silico that we believe is driven by extensive co-trimoxazole and sulfadoxine/pyrimethamine use. More than one-third of pneumococci employ a novel mechanism of co-trimoxazole resistance. Resistance has now reached a point of stabilizing evolution. The use of co-trimoxazole to prevent pneumococcal infection in HIV/AIDS patients in sub-Saharan Africa should be re-evaluated.
Project description:Intermittent treatment with sulfadoxine-pyrimethamine is widely recommended for the prevention of malaria in pregnant women in Africa. However, with the spread of resistance to sulfadoxine-pyrimethamine, new interventions are needed.We conducted a double-blind, randomized, controlled trial involving 300 human immunodeficiency virus (HIV)-uninfected pregnant adolescents or women in Uganda, where sulfadoxine-pyrimethamine resistance is widespread. We randomly assigned participants to a sulfadoxine-pyrimethamine regimen (106 participants), a three-dose dihydroartemisinin-piperaquine regimen (94 participants), or a monthly dihydroartemisinin-piperaquine regimen (100 participants). The primary outcome was the prevalence of histopathologically confirmed placental malaria.The prevalence of histopathologically confirmed placental malaria was significantly higher in the sulfadoxine-pyrimethamine group (50.0%) than in the three-dose dihydroartemisinin-piperaquine group (34.1%, P=0.03) or the monthly dihydroartemisinin-piperaquine group (27.1%, P=0.001). The prevalence of a composite adverse birth outcome was lower in the monthly dihydroartemisinin-piperaquine group (9.2%) than in the sulfadoxine-pyrimethamine group (18.6%, P=0.05) or the three-dose dihydroartemisinin-piperaquine group (21.3%, P=0.02). During pregnancy, the incidence of symptomatic malaria was significantly higher in the sulfadoxine-pyrimethamine group (41 episodes over 43.0 person-years at risk) than in the three-dose dihydroartemisinin-piperaquine group (12 episodes over 38.2 person-years at risk, P=0.001) or the monthly dihydroartemisinin-piperaquine group (0 episodes over 42.3 person-years at risk, P<0.001), as was the prevalence of parasitemia (40.5% in the sulfadoxine-pyrimethamine group vs. 16.6% in the three-dose dihydroartemisinin-piperaquine group [P<0.001] and 5.2% in the monthly dihydroartemisinin-piperaquine group [P<0.001]). In each treatment group, the risk of vomiting after administration of any dose of the study agents was less than 0.4%, and there were no significant differences among the groups in the risk of adverse events.The burden of malaria in pregnancy was significantly lower among adolescent girls or women who received intermittent preventive treatment with dihydroartemisinin-piperaquine than among those who received sulfadoxine-pyrimethamine, and monthly treatment with dihydroartemisinin-piperaquine was superior to three-dose dihydroartemisinin-piperaquine with regard to several outcomes. (Funded by the Eunice Kennedy Shriver National Institute of Child Health and Human Development; ClinicalTrials.gov number, NCT02163447.).
Project description:BACKGROUND:About 80% of all reported sickle cell disease (SCD) cases in children anually are recorded in Africa. Although malaria is considered a major cause of death in SCD children, there is limited data on the safety and effectiveness of the available antimalarial drugs used for prophylaxis. Also, previous systematic reviews have not provided quantitative measures of preventive effectiveness. The purpose of this research was to conduct a systematic review and meta-analysis of the available literature to determine the safety and effectiveness of antimalarial chemoprophylaxis used in SCD patients. METHODS:We searched in PubMed, Medline, CINAHL, POPLine and Cochrane library, for the period spanning January 1990 to April 2018. We considered randomized or quasi-randomized controlled trials comparing any antimalarial chemoprophylaxis to, 1) other antimalarial chemoprophylaxis, 2) placebo or 3) no intervention, in SCD patients. Studies comparing at least two treatment arms, for a minimum duration of three months, with no restriction on the number of patients per arm were reviewed. The data were extracted and expressed as odds ratios. Direct pairwise comparisons were performed using fixed effect models and the heterogeneity assessed using the I-square. RESULTS:Six qualified studies that highlighted the importance of antimalarial chemoprophylaxis in SCD children were identified. In total, seven different interventions (Chloroquine, Mefloquine, Mefloquine artesunate, Proguanil, Pyrimethamine, Sulfadoxine-pyrimethamine, Sulfadoxine-pyrimethamine amodiaquine) were evaluated in 912 children with SCD. Overall, the meta-analysis showed that antimalarial chemoprophylaxis provided protection against parasitemia and clinical malaria episodes in children with SCD. Nevertheless, the risk of hospitalization (OR?=?0.72, 95% CI?=?0.267-1.959; I2 =?0.0%), blood transfusion (OR?=?0.83, 95% CI?=?0.542-1.280; I2 =?29.733%), vaso-occlusive crisis (OR?=?19, 95% CI?=?1.713-2.792; I2 =?93.637%), and mortality (OR?=?0.511, 95% CI?=?0.189-1.384; I2 =?0.0%) did not differ between the intervention and placebo groups. CONCLUSION:The data shows that antimalarial prophylaxis reduces the incidence of clinical malaria in children with SCD. However, there was no difference between the occurrence of adverse events in children who received placebo and those who received prophylaxis. This creates an urgent need to assess the efficacy of new antimalarial drug regimens as potential prophylactic agents in SCD patients. SYSTEMATIC REVIEW REGISTRATION:PROSPERO (CRD42016052514).
Project description:BACKGROUND:Sulfadoxine-pyrimethamine resistance threatens efficacy of intermittent preventive treatment of malaria during pregnancy, and alternative regimens need to be identified. With the return of chloroquine efficacy in southern Africa, we postulated that chloroquine either as an intermittent therapy or as weekly chemoprophylaxis would be more efficacious than intermittent sulfadoxine-pyrimethamine for prevention of malaria in pregnancy and associated maternal and newborn adverse outcomes. METHODS:We did an open-label, single-centre, randomised controlled trial at Ndirande Health Centre, Blantyre, in southern Malawi. We enrolled pregnant women (first or second pregnancy) at 20-28 weeks' gestation who were HIV negative. Participants were randomly assigned in a 1:1:1 ratio using a computer-generated list to either intermittent sulfadoxine-pyrimethamine (two doses of 1500 mg sulfadoxine and 75 mg pyrimethamine, 4 weeks apart), intermittent chloroquine (two doses of 600 mg on day 1, 600 mg on day 2, and 300 mg on day 3), or chloroquine prophylaxis (600 mg on day 1 then 300 mg every week). The primary endpoint was placental malaria in the modified intent-to-treat population, which consisted of participants who contributed placental histopathology data at birth. Secondary outcomes included clinical malaria, maternal anaemia, low birthweight, and safety. This trial is registered with ClinicalTrials.gov, number NCT01443130. FINDINGS:Between February, 2012, and May, 2014, we enrolled and randomly allocated 900 women, of whom 765 contributed histopathological data and were included in the primary analysis. 108 (14%) women had placental malaria, which was lower than the anticipated prevalence of placental malaria infection. Protection from placental malaria was not improved by chloroquine as either prophylaxis (30 [12%] of 259 had positive histopathology; relative risk [RR] 0·75, 95% CI 0·48-1·17) or intermittent therapy (39 [15%] of 253; RR 1·00, 0·67-1·50) compared with intermittent sulfadoxine-pyrimethamine (39 [15%] of 253). In protocol-specified analyses adjusted for maternal age, gestational age at enrolment, bednet use the night before enrolment, anaemia at enrolment, and malaria infection at enrolment, women taking chloroquine as prophylaxis had 34% lower placental infections than did those allocated intermittent sulfadoxine-pyrimethamine (RR 0·66, 95% CI 0·46-0·95). Clinical malaria was reported in nine women assigned intermittent sulfadoxine-pyrimethamine, four allocated intermittent chloroquine (p=0·26), and two allocated chloroquine prophylaxis (p=0·063). Maternal anaemia was noted in five women assigned intermittent sulfadoxine-pyrimethamine, 15 allocated intermittent chloroquine (p=0·038), and six assigned chloroquine prophylaxis (p>0·99). Low birthweight was recorded for 31 babies born to women allocated intermittent sulfadoxine-pyrimethamine, 29 assigned intermittent chloroquine (p=0·78), and 41 allocated chloroquine prophylaxis (p=0·28). Four women assigned intermittent sulfadoxine-pyrimethamine had adverse events possibly related to study product compared with 94 women allocated intermittent chloroquine (p<0·0001) and 26 allocated chloroquine prophylaxis (p<0·0001). Three women had severe or life-threatening adverse events related to study product, of whom all were assigned intermittent chloroquine (p=0·25). INTERPRETATION:Chloroquine administered as intermittent therapy did not provide better protection from malaria and related adverse effects compared with intermittent sulfadoxine-pyrimethamine in a setting of high resistance to sulfadoxine-pyrimethamine. Chloroquine chemoprophylaxis might provide benefit in protecting against malaria during pregnancy, but studies with larger sample sizes are needed to confirm these results. FUNDING:US National Institutes of Health.
Project description:BACKGROUND:Trials of intermittent preventive treatment (IPTp) of malaria in pregnant women that compared dihydroartemisinin-piperaquine with the standard of care, sulfadoxine-pyrimethamine, showed dihydroartemisinin-piperaquine was superior at preventing malaria infection, but not at improving birthweight. We aimed to assess whether sulfadoxine-pyrimethamine shows greater non-malarial benefits for birth outcomes than does dihydroartemisinin-piperaquine, and whether dihydroartemisinin-piperaquine shows greater antimalarial benefits for birth outcomes than does sulfadoxine-pyrimethamine. METHODS:We defined treatment as random assignment to sulfadoxine-pyrimethamine or dihydroartemisinin-piperaquine before pooling individual participant-level data from 1617 HIV-uninfected pregnant women in Kenya (one trial; n=806) and Uganda (two trials; n=811). We quantified the relative effect of treatment on birthweight (primary outcome) attributed to preventing placental malaria infection (mediator). We estimated antimalarial (indirect) and non-malarial (direct) effects of IPTp on birth outcomes using causal mediation analyses, accounting for confounders. We used two-stage individual participant data meta-analyses to calculate pooled-effect sizes. FINDINGS:Overall, birthweight was higher among neonates of women randomly assigned to sulfadoxine-pyrimethamine compared with women assigned to dihydroartemisinin-piperaquine (mean difference 69 g, 95% CI 26 to 112), despite placental malaria infection being lower in the dihydroartemisinin-piperaquine group (relative risk [RR] 0·64, 95% CI 0·39 to 1·04). Mediation analyses showed sulfadoxine-pyrimethamine conferred a greater non-malarial effect than did dihydroartemisinin-piperaquine (mean difference 87 g, 95% CI 43 to 131), whereas dihydroartemisinin-piperaquine conferred a slightly larger antimalarial effect than did sulfadoxine-pyrimethamine (8 g, -9 to 26), although more frequent dosing increased the antimalarial effect (31 g, 3 to 60). INTERPRETATION:IPTp with sulfadoxine-pyrimethamine appears to have potent non-malarial effects on birthweight. Further research is needed to evaluate monthly dihydroartemisinin-piperaquine with sulfadoxine-pyrimethamine (or another compound with non-malarial effects) to achieve greater protection against malarial and non-malarial causes of low birthweight. FUNDING:Eunice Kennedy Shriver National Institute of Child Health and Human Development, Bill & Melinda Gates Foundation, and Worldwide Antimalarial Resistance Network.
Project description:BACKGROUND:Intermittent preventive treatment is recommended for pregnant women living in malaria endemic countries due to benefits for both mother and baby. However, the impact may not be the same in HIV-positive pregnant women, as HIV infection impairs a woman's immunity. OBJECTIVES:To compare intermittent preventive treatment regimens for malaria in HIV-positive pregnant women living in malaria-endemic areas. SEARCH STRATEGY:In June 2011, we searched the Cochrane Infectious Diseases Group Specialized Register, CENTRAL, MEDLINE; EMBASE; LILACS, the metaRegister of Controlled Trials (mRCT), reference lists and conference abstracts. We also contacted researchers and organizations for information on relevant trials. SELECTION CRITERIA:Randomized controlled trials comparing different intermittent preventive treatment regimens for preventing malaria in HIV-positive pregnant women in malaria-endemic areas. DATA COLLECTION AND ANALYSIS:Two authors extracted data and assessed risk bias. Dichotomous variables were combined using risk ratios (RR) and mean differences (MD) for continuous outcomes, both with 95% confidence intervals (CI). MAIN RESULTS:Two randomized trials with 722 HIV-positive pregnant women were included, comparing monthly regimens of sulfadoxine-pyrimethamine (SP) to the standard 2-dose regimen in the second and third trimesters. There were no statistically significant differences between monthly SP and 2-dose SP in rates of maternal anaemia, low birth weight, and neonatal mortality. In primigravidae and secondigravidiae, the monthly regimen was associated with less placental parasitaemia (RR 0.38, 95% CI 0.21 to 0.70, two trials) and less peripheral parasitaemia (RR 0.25, 95% CI 0.14 to 0.43, two trials), but no effect was demonstrated in multigravid women. Babies born to primigravidae and secundigravida women on monthly SP had a higher mean birth weight (weighted mean difference (WMD) 130 g; 95% CI 120 g to 150 g, two trials) than babies born to mothers on 2-dose SP. Multigravidae women treated with monthly SP had significant higher haemoglobin level than those treated with treated 2 dose SP (WMD 0.21 g/dL, 95% CI 0.15 g/dL to 0.27 g/dL, one trial). There were no trials that assessed other treatment regimens for intermittent preventive treatment in HIV-positive pregnant women. AUTHORS' CONCLUSIONS:Three or more doses of SP is superior to the standard two doses in HIV-positive pregnant women. However, since SP cannot be administered concurrently with co-trimoxazole - a drug often recommended for infection prophylaxis in HIV-positive pregnant women, new drugs and research is needed to address needs of HIV-positive pregnant women.
Project description:BACKGROUND:Pneumocystis pneumonia (PCP) is a disease affecting immunocompromised patients. PCP among these patients is associated with significant morbidity and mortality. OBJECTIVES:To assess the effectiveness of PCP prophylaxis among non-HIV immunocompromised patients; and to define the type of immunocompromised patient for whom evidence suggests a benefit for PCP prophylaxis. SEARCH METHODS:Electronic searches of the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2014, Issue 1), MEDLINE and EMBASE (to March 2014), LILACS (to March 2014), relevant conference proceedings; and references of identified trials. SELECTION CRITERIA:Randomised controlled trials (RCTs) or quasi-RCTs comparing prophylaxis with an antibiotic effective against PCP versus placebo, no intervention, or antibiotic(s) with no activity against PCP; and trials comparing different antibiotics effective against PCP among immunocompromised non-HIV patients. We only included trials in which Pneumocystis infections were available as an outcome. DATA COLLECTION AND ANALYSIS:Two review authors independently assessed risk of bias in each trial and extracted data from the included trials. We contacted authors of the included trials to obtain missing data. The primary outcome was documented PCP infections. Risk ratios (RR) with 95% confidence intervals (CI) were estimated and pooled using the random-effects model. MAIN RESULTS:Thirteen trials performed between the years 1974 and 2008 were included, involving 1412 patients. Four trials included 520 children with acute lymphoblastic leukemia and the remaining trials included adults with acute leukemia, solid organ transplantation or autologous bone marrow transplantation. Compared to no treatment or treatment with fluoroquinolones (inactive against Pneumocystis), there was an 85% reduction in the occurrence of PCP in patients receiving prophylaxis with trimethoprim/sulfamethoxazole, RR of 0.15 (95% CI 0.04 to 0.62; 10 trials, 1000 patients). The evidence was graded as moderate due to possible risk of bias. PCP-related mortality was also significantly reduced, RR of 0.17 (95% CI 0.03 to 0.94; nine trials, 886 patients) (low quality of evidence due to possible risk of bias and imprecision), but in trials comparing PCP prophylaxis against placebo or no treatment there was no significant effect on all-cause mortality (low quality of evidence due to imprecision). Occurrence of leukopenia or neutropenia and their duration were not reported consistently. No significant differences in overall adverse events or events requiring discontinuation were seen comparing trimethoprim/sulfamethoxazole to no treatment or placebo (four trials, 470 patients, moderate quality evidence). No differences between once daily versus thrice weekly trimethoprim/sulfamethoxazole were seen (two trials, 207 patients). AUTHORS' CONCLUSIONS:Given an event rate of 6.2% in the control groups of the included trials, prophylaxis for PCP using trimethoprim/sulfamethoxazole is highly effective among non-HIV immunocompromised patients, with a number needed to treat to prevent PCP of 19 patients (95% CI 17 to 42). Prophylaxis should be considered for patients with a similar baseline risk of PCP.
Project description:BACKGROUND:Asymptomatic falciparum malaria is associated with poorer cognitive performance in African schoolchildren and intermittent preventive treatment of malaria improves cognitive outcomes. However, the developmental benefits of chemoprevention in early childhood are unknown. Early child development was evaluated as a major outcome in an open-label, randomized, clinical trial of anti-malarial chemoprevention in an area of intense, year-round transmission in Uganda. METHODS:Infants were randomized to one of four treatment arms: no chemoprevention, daily trimethoprim-sulfamethoxazole, monthly sulfadoxine-pyrimethamine, or monthly dihydroartemisinin-piperaquine (DP), to be given between enrollment (4-6 mos) and 24 months of age. Number of malaria episodes, anaemia (Hb < 10) and neurodevelopment [Mullen Scales of Early Learning (MSEL)] were assessed at 2 years (N = 469) and at 3 years of age (N = 453); at enrollment 70 % were HIV-unexposed uninfected (HUU) and 30 % were HIV-exposed uninfected (HEU). RESULTS:DP was highly protective against malaria and anaemia, although trial arm was not associated with MSEL outcomes. Across all treatment arms, episodes of malarial illness were negatively predictive of MSEL cognitive performance both at 2 and 3 years of age (P = 0.02). This relationship was mediated by episodes of anaemia. This regression model was stronger for the HEU than for the HUU cohort. Compared to HUU, HEU was significantly poorer on MSEL receptive language development irrespective of malaria and anaemia (P = 0.01). CONCLUSIONS:Malaria with anaemia and HIV exposure are significant risk factors for poor early childhood neurodevelopment in malaria-endemic areas in rural Africa. Because of this, comprehensive and cost/effective intervention is needed for malaria prevention in very young children in these settings.
Project description:New regimens for intermittent preventive treatment in pregnancy (IPTp) against malaria are needed as the effectiveness of the standard two-dose sulfadoxine-pyrimethamine (SP) regimen is under threat. Previous trials have shown that IPTp with monthly SP benefits HIV-positive primi- and secundigravidae, but there is no conclusive evidence of the possible benefits of this regimen to HIV-negative women, or to a population comprising of both HIV-positive and -negative women of different gravidities.This study analyzed 484 samples collected at delivery as part of a randomized, partially placebo controlled clinical trial, conducted in rural Malawi between 2003 and 2007. The study included pregnant women regardless of their gravidity or HIV-infection status. The participants received SP twice (controls), monthly SP, or monthly SP and two doses of azithromycin (AZI-SP). The main outcome was the prevalence of peripheral Plasmodium falciparum malaria at delivery diagnosed with a real-time polymerase chain reaction (PCR) assay.Overall prevalence of PCR-diagnosed peripheral P. falciparum malaria at delivery was 10.5%. Compared with the controls, participants in the monthly SP group had a risk ratio (95% CI) of 0.33 (0.17 to 0.64, P<0.001) and those in the AZI-SP group 0.23 (0.11 to 0.48, P<0.001) for malaria at delivery. When only HIV-negative participants were analyzed, the corresponding figures were 0.26 (0.12 to 0.57, P<0.001) for women in the monthly SP group, and 0.24 (0.11 to 0.53, P<0.001) for those in the AZI-SP group.Our results suggest that increasing the frequency of SP administration during pregnancy improves the efficacy against malaria at delivery among HIV-negative women, as well as a population consisting of both HIV-positive and -negative pregnant women of all gravidities, in a setting of relatively low but holoendemic malaria transmission, frequent use of bed nets and high SP resistance.