In the 1960s, the World Health Organization(WHO) began a campaign te eradicate the mosquitoes thattransmit the disease malaria. It was a noble goal, since malaria kills an estimated 3 million people each yearin the world's tropical regions, predominantly southern Africa, WHO led an effort to spray the mosquitoes'habitat with a chemical pesticide- a poison used to kill insects- called DDT. Early results were promising,and the mosquito was eliminated from the edge of its native range. The effort soon faltered, however, and theeradication was dropped. How could a tiny mosquitoes thwart the best efforts of a large group of well-“nội dung được trích dẫn từ 123doc.org - cộng đồng mua bán chia sẻ tài liệu hàng đầu Việt Nam”
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