A Study of the Impact of Insecticide-treated Curtains on the Prevalence of Antimalarial Drug Resistance in Children With Uncomplicated Malaria in Burkina Faso
试验速览
- 阶段
- 不适用
- 状态
- 已完成
- 入组人数
- 1,035
- 试验地点
- 2
- 主要终点
- Clinical and parasitological failure rates by day 14
研究概览
简要总结
Attempts to understand the relationship malaria transmission intensity and antimalarial drug resistance had rested mainly on mathematical models. To date, except for two studies which reported reductions in the prevalence of drug resistance in Tanzania and Zimbabwe, no other field data addressed the impact of reducing malaria transmission by the use of vector control measures on antimalarial drug resistance. Thus whether vector control decrease or increase drug resistance remains a contentious issue. The aim of this study was to investigate the impact of insecticide-treated curtains (ITCs) on clinical and parasitological outcomes in children with uncomplicated malaria treated with chloroquine (CQ), on the prevalence of genetic markers of resistance to CQ and sulphadoxine-pyrimethamine (SP) and on the ability of children to clear drug resistant parasites. The therapeutic efficacy of CQ was studied in 9 villages which used ITCs for 6-8 years and 9 villages with no history of ITC use. A cross-sectional survey was also conducted to estimate the prevalence of genetic markers of resistance to CQ and SP in asymptomatic children.
详细描述
- Background
Drug resistance has been associated with increased numbers of hospital admissions, increased cases of clinical malaria and malaria-specific mortality . Several strategies have been proposed as means by which the spread of antimalarial drugs resistance could be delayed. These strategies include reducing drug pressure, improving the quality of drug use, using combinations of antimalarial drugs and use of vector control measures. Restricting the use of drugs to reduce drug pressure is presently unrealistic due to poor access to health facilities and a lack of equipment. Improving the quality of use of antimalarials through the use of pre-packaged doses, education and training is a sound control strategy. However, the impact of this strategy on drug resistance has not yet been evaluated. Another promising approach to contain drug resistance is the use of combination therapies. The most successful combinations so far are those using artemisinin and its derivatives. It is likely that implementing combination therapy in resource limited countries will be hampered by its high cost. Given their impact in reducing malaria transmission, cases of clinical malaria and all-cause malaria mortality, insecticide-treated materials (ITMs) have recently been proposed as a potential tool for delaying the development and spread of drug resistance. So far, the debate on the interaction between malaria transmission intensity and drug resistance has been driven by analytical models and, to our knowledge, only 2 field studies have yet addressed the impact of ITMs on antimalarial drug resistance. If ITMs reduced the development and spread of antimalarial drug resistance, this would enhance their usefulness as a malaria control tool. This study examines the impact of insecticide-treated curtains (ITC)used over 6-8 years on the prevalence of antimalarial drug resistance in Burkina Faso. 2. Objectives
2.1 Primary objectives
- To determine the frequency of in vivo clinical and parasitological failures following treatment of uncomplicated malaria with CQ in children living in villages protected and not protected by insecticide treated curtains (ITC).
- To determine if children in ITC and non-ITC villages with clinical malaria differ in their ability to clear genetically resistant parasites after treatment with CQ.
2.2 Secondary objectives
- To determine the proportions of children infected with parasites carrying the pfcrt-76T and pfmdr1-86Y alleles associated with resistance to CQ in villages protected and not protected by ITC.
- To determine the proportions of children infected with parasites carrying parasites with the dihydrofolate reductase (dhfr) and dihydropteroate synthetase (dhps) alleles associated with resistant to SP in ITC and non- ITC protected villages.
- To relate in vivo clinical and parasitological failure rates to the presence of genotypic markers of resistance to CQ by estimating genotype-failure indices (GFIs) and genotype-resistance indices (GRIs).
- Methods
3.1 Field work
研究设计
- 研究类型
- Interventional
- 分配方式
- Non Randomized
- 干预模型
- Single Group
- 主要目的
- Treatment
- 盲法
- None
入排标准
- 年龄范围
- 6 Months 至 59 Months（Child）
- 性别
- All
- 接受健康志愿者
- 否
入选标准
- •Age between 6 and 59 months Mono infection with P.falciparum malaria, with parasitaemia in the range of 1,000 to 150,000 parasites per ml Absence of danger signs or signs of severe malaria. Axillary temperature >= 37.5 ºC. Absence of signs of severe malnutrition. Absence of any obvious cause of fever other than malaria. No history of allergy to CQ. Willingness to return to the health facility for follow-up. Informed consent obtained from the caretaker of the child
排除标准
- •Danger signs of severe or complicated malaria, persisted vomiting. Received treatment with an antimalarial drug other than CQ in the last 2 weeks. Caretaker did not sign the consent form
结局指标
主要结局
Clinical and parasitological failure rates by day 14
Prevalence of pfcrt-76T, pfmdr1-86Y before treatment
次要结局
- Proportion of children who cleared parasites carrying pfcrt-76T and pfmdr1-86Y alleles.
- Prevalence of dhfr-51, 59, 108 and dhps-437, 540
研究者
Brian Greenwood
Professor
London School of Hygiene and Tropical Medicine