首页
外语
计算机
考研
公务员
职业资格
财经
工程
司法
医学
专升本
自考
实用职业技能
登录
外语
Climate Change May Make Insect-Borne Diseases Harder to Control Climate change can influence how infectious diseases affect
Climate Change May Make Insect-Borne Diseases Harder to Control Climate change can influence how infectious diseases affect
admin
2013-09-24
28
问题
Climate Change May Make Insect-Borne Diseases Harder to Control
Climate change can influence how infectious diseases affect the world, particularly illnesses spread by vector(传染媒介)like mosquitoes. Now scientists have developed some understanding about how rainfall and temperature can influence malaria, dengue(登革热)and West Nile virus infections as well as ways to combat them.
Vector-borne diseases are among the most complex and annoying illnesses to manage, since so many elements are at play, like host resistance, the environment, urbanization and the pathogens(病原体)themselves. As a result, it’s difficult to tease out any one factor to measure, and with the added effects of warming weather and shifting precipitation(降水), ongoing disease-management efforts are becoming more complicated.
"Climate change is not going to invent any new diseases! it’s going to make controlling existing diseases harder," said Diarmid Campbell-Lendrum, head of the climate change team at the World Health Organization’s headquarters. "We’ve been describing the links between climate change and health for quite a long time."
Diseases spread by mosquitoes are particularly affected by climate change, since the insects lay their eggs in standing water, be it in puddles, ponds, lakes or tide pools. Standing water varies with rainfall, humidity and temperature, with wetter weather typically showing a greater number of mosquitoes. When a female mosquito matures, she can spread infections by drawing blood from an infected host and transmitting the illness to a different host with another bite.
Heat can also influence how a pathogen is spread. In the case of West Nile virus, rising temperatures work both in favor of and against the spread of the disease. "The pathogen—the warmer the temperature, the faster it moves from the blood to being transmitted. It usually takes a while for the virus to get into the mosquito’s salivary glands," said Marm Kilpatrick, an assistant professor in ecology and evolutionary biology at the University of California, Santa Cruz. "The biting rate also gets faster. So those things are all going to give you more transmission. "
On the other hand, hotter weather shortens the mosquito’s life span. "What you basically have going on is three factors going in one direction and one factor in the other direction," said Kilpatrick, who published a paper on West Nile virus last month in the journal Science. "It’s a little bit tricky to make a solid prediction."
West Nile virus is an interesting case study because the disease originated in Africa and emerged in North America in 1999, relatively recently as far as diseases go. Because of this, researchers have tracked where the disease has spread over time. Kilpatrick found that the virus is most abundant in human-developed areas like cities and farms. He also found that the virus quickly adapted to use local mosquitoes in the United States, and hosts like robins played an important role in spreading the virus over long distances.
However, Kilpatrick hesitates to link climate change directly to yearly changes in West Nile infection rates, since land use changes and infected hosts move around. Nonetheless, lessons from climate change and West Nile can be applied to more prevalent diseases. "The same questions we’re wondering about West Nile apply to malaria and dengue," said Kilpatrick.
A killer with no cure spreads
Dengue fever is one of the world’s most common diseases, with one-third of the world living in endemic areas(病区), according to the US Centers for Disease Control and Prevention. It afflicts 900 million people worldwide, and the number is growing, according to Khoa T. D. Thai, a researcher at the Academic Medical Center in Amsterdam and at the Oxford University Clinical Research Unit in Ho Chi Minh City in Vietnam.
Thai, who co-authored a paper on dengue this past summer in Experimental Biology and Medicine, said that the number of people afflicted by the disease is increasing, but part of the rise comes from more awareness and better diagnostics(诊断法)as health care reaches impoverished and rural areas.
The distribution of the disease is also growing, some of which Thai attributes to climate change as regions with tropical climates expand. Since dengue has no cure or vaccine, fighting the disease must focus mainly on prevention, whether it’s draining water to prevent mosquitoes from breeding or wearing long sleeves and using mosquito repellents.
Anticipating climate trends is also important in fighting mosquito-borne diseases, particularly with malaria. "The key step to all of this is to understand what happens with climate variability," said Andy Dobson, a professor of ecology and evolutionary biology at Princeton University. "Although we’ve got some fantastic weather data, it’s always being cleaned up. In general we need much better models for how climate variability affects malaria."
Getting ahead of malaria shifts from climate change is important because people who have been exposed to the parasite(寄生物)the most have the strongest resistance to it, said Dobson, who wrote about this topic in Trends in Ecology and Evolution in June. As the disease moves to new areas, previously unexposed populations may experience an epidemic.
"Malaria will expand particularly in the mountain regions. We’ve seen increasingly strong evidence of that in the east African highlands," he said, noting how drought and rainfall have shifted and warming weather has made mountains more welcoming to mosquitoes.
"Malaria will always come from an interaction between temperature and rainfall," added Dobson. "The rainfall certainly determines the mosquito abundance, and temperature affects the parasites. "
Dobson said it is more efficient to combat malaria by using mosquito nets and managing the environment rather than some of the more exotic proposed control measures like lasers to shoot mosquitoes. "Understanding the ecological dynamics of the disease will get you much more bang for your buck," he said. With better climate predictions and land management, Dobson said malaria and other vector-borne diseases can be reduced significantly.
Kilpatrick hesitates to link climate change to West Nile infection rates because of______.
选项
A、the changes in the number of mosquitoes
B、the difficulty of counting infected people
C、the endurance of the West Nile virus to heat
D、the uncertainty of land use and infected hosts
答案
D
解析
同义转述题。定位句表明,Kilpatrick不愿将气候变化与西尼罗河病毒传染率每年的变化直接联系起来,因为土地使用在变化,并且被病毒感染的宿主也在四处流动。因此,D)“土地使用和被感染的宿主的不确定”符合原文意思。
转载请注明原文地址:https://jikaoti.com/ti/UIQFFFFM
0
大学英语四级
相关试题推荐
A、TaughtherEnglishherself.B、Wenttotalkwithherteacher.C、Signedupforalanguagetrainingclassforher.D、Talkedwith
WhenMomandDadGrowOldTheprospectoftalkingtoincreasinglyfragileparentsabouttheirfuturecanbe"oneofthemost
A、Einsteinwasafamouschemist.B、EinsteinwaspopularinAmerica.C、Einsteinheadedaresearchinstitute.D、Einsteinenjoyedr
WethoughtMarywouldpassandJohnwouldfail,______(但与预期的相反)itwastheotherbutcontrarytoexpectation
There’snoquestionthattheEarthisgettinghotter.Therealquestionsare:Howmuchofthewarmingisourfault,andarewe【S
A、Themanwenttoawrongcheckincounter.B、Themanhasjustmissedhisflight.C、Theplanewillleaveat9:14.D、Theplane’sd
ProfessorWhitefrequentlyremindsmeto______myselfofeverychancetoimprovemyEnglish.
______superstitiousbeliefsaboutthemandrakeplant.
A、ForestspeaksnoEnglish.B、Gloriawaspoorinrememberingthings.C、Theycannotcommunicateinonelanguage.D、Theywerelest
Humanbeingsareneversatisfied.Theyhavealwayswantedthingstobeeasier,faster,morecomfortableormore【B1】______.Human
随机试题
患者男,1岁,诊断为右侧睾丸鞘膜积液,最佳治疗方案是
男性,26岁。因误服毒物1小时而出现头晕、头痛、多汗、恶心、呕吐、腹痛、腹泻等症状。体格检查:两肺湿啰音,呼吸有蒜味,意识清楚。利用氯磷定抢救患者的作用机制是
A.ALT明显升高B.血氨明显升高C.BUN明显升高D.UA明显升高E.ALP明显升高阻塞性黄疸可见()
现代物流最基本的特征就是用系统的思想将原来分散的各功能要素加以整合,使之成为一个有机的整体。()
因进出口货物的品名申报不实而影响国家税款征收的,应处()。
某企业为单步骤简单生产企业,设有一个基本生产车间,连续大量生产甲、乙两种产品,采用品种法计算产品成本。另设有一个供电车间,为全厂提供供电服务,供电车间的费用全部通过“辅助生产成本"归集核算。2017年12月份有关成本费用资料如下:(1)12月份发出材料
关于我国互联网金融的说法正确的是()。
Genetherapyandgene-baseddrugsaretwowayswecouldbenefitfromourgrowingmasteryofgeneticscience.Buttherewillbeo
在异步串行通信中,使用波特率来表示数据的传送速率,它是指______。
【T1】TheagreementisoverseenbytheCommitteeonAgriculturewhichreviewsprogressintheimplementationofcommitments,andi
最新回复
(
0
)