[填空题]Questions 47 to 56 are based on the following passage.
Every year, malaria (疟疾) (47) about five hundred million people. More than one million of them die, mostly young children and pregnant women in Africa. For several years in sub-Saharan Africa, the Global Fund and other groups have been (48) for bed nets treated with long-lasting insect poison. Malaria is (49) by mosquito bites. The groups have also invested in anti--malaria drugs for A. C. T. , artemisinin-based combination therapy (青蒿素的组合疗法) .
Recently, a team from the World Health organization visited Ethiopia (埃塞俄比亚) , Ghana (加纳) , Rwanda (卢旺达) and Zambia (赞比亚) . These countries were the first to (50) the bed nets and medicine. The Global Fund to Fight AIDS, Tuberculosis (结核) and Malaria requested a study to see if the interventions were (51) .
The researchers found that the answer is yes. They looked at records of children (52) five. They found th