Scientists Find a New Way To Kill Disease-Carrying Mosquitoes
Scientists say they have killed nearly all the disease-carrying mosquitoes on two islands in China using a new method.
That is the good news.
The bad news is that the method may cost a lot of money and not work as well in larger areas.
In the experiment, researchers targeted Asian tiger mosquitoes. The insects have white stripes and can spread dengue fever, Zika and other diseases.
To limit the insects' ability to reproduce, scientists first infected a group of mosquitoes with a kind of virus-fighting bacteria. Then they hit them with a small amount of radiation.
The affected mosquitoes were then released onto two small islands near Guangzhou, China. The area suffers from dengue fever.
The scientists reported that, following the insects' release, the number of female mosquitoes responsible for spreading dengue fever dropped by 83 to 94 percent each year.
That drop is similar to what happens after spraying insecticide or using mosquitoes whose genes have been changed.
At times, the new method worked even better than that. Some weeks, researchers saw no signs of disease-carrying mosquitoes.
Zhiyong Xi is with Michigan State University. He led the research team. Xi said that no other mosquito control method has had that kind of total success.
But to achieve that success, researchers had to introduce lots of new mosquitoes onto the islands – up to 4 million each week, over 18 weeks.
Scott O'Neill of the World Mosquito Program says the number of insects needed to control mosquitoes this way is likely too large for most areas.
Biologist Brian Lovett also had concerns. He is with the University of Maryland, just outside Washington, D.C. Lovett said, "You have to keep doing it."
If the process is not repeated, new mosquitoes come in or grow up to replace those that died. Repeating the process could be very costly, Lovett noted.
Researchers from the experiment say the cost will go down as the technology improves. They estimate the cost will soon be about the same as pest sterilization methods, and less costly than some insecticides.
The team is working on a mosquito-control project in an area about four times larger than the islands they used two years ago. Their findings from that first experiment appeared this month in the journal Nature.
I'm Kelly Jean Kelly.
1.as well 也
He should pay and maintain you as well.
2.go down 下降
I went down on my knees and prayed for guidance.
3.grow up 成长
All plants like to grow up towards the sunlight.
4.dengue fever 登革热
Dengue fever is an acute viral disease caused by the Dengue virus.
5.To limit the insects' ability to reproduce, scientists first infected a group of mosquitoes with a kind of virus-fighting bacteria.
a group of 一组
Suddenly the door opened and a group of children burst in.
I came across a group of children playing.
6.At times, the new method worked even better than that.
At times 有时
I think the reformers have at times oversold the reforms.
I found Ben's cynicism wearing at times.
习志勇就职于密歇根州立大学。他领导了这一研究小组 。习志勇表示，其他的蚊子控制法尚未取得如此彻底的成功 。
生物学家布莱恩·洛维特（Brian Lovett）也对此表示担忧。他就职于华盛顿特区外的马里兰大学 。洛维特说：“你必须得不间断地进行 。”