禽疟与气候变化

 　　Malaria 1 and Climate Change Bite the birds

　　Malaria among birds is becoming more prevalent
　　鸟类中的疟疾感染越来越多
　　MOSQUITOES, which carry malaria parasites 3, like the warm and wet conditions that are expected to become more common with climate change. This has led many to reason that malarial 4 infections will increase. Yet studies run into the unreliability of modelling future climatic effects and sometimes ignore changes in land use and health care. However, a new analysis of the spread of avian malaria shows that for the birds, at least, there is a real worry.
　　携带疟原虫的蚊子喜欢温暖潮湿的环境，由于气候变化的影响这种环境可能会越来越普遍。 因此很多人推论，疟疾感染将会增加。 但是很多研究遇到了未来气候效应模型不可靠的问题，而且有时忽视了土地使用和健康保健方面的变化。 然而，一项新的对禽疟传播的分析显示，至少对于鸟类而言，真正令人担忧的状况已经出现。
　　Laszlo Garamszegi, of the Do?ana Biological Station in Spain, studied patterns of malarial infections in birds to avoid confounding human factors in determining the epidemiology of a closely related parasite 2. He looked at 43 previous studies that had carefully screened 3,000 bird species for malaria in different locations over the past 70 years. He found that an increase in global temperatures of 1°C was accompanied by a two-to threefold increase in the average prevalence of malaria in birds. The most dramatic increases took place during the past 20 years.
　　在对一种有密切关系的寄生虫进行流行病学鉴定时，为避免混入人为因素，西班牙多尼亚纳生物站的喇撒?噶母赛棘研究了在鸟类中疟疾感染的模式。 他察看了以前的43份研究。这些研究仔细鉴别了过去70年来在不同地区的3000中鸟类感染疟疾的情况。 他发现，全球气温每增加1°C，鸟类平均疟疾患病率随之增加两到三倍。 最急剧地增加是发生在过去的20年间。
　　Dr Garamszegi's work, published in Global Change Biology, found that the house sparrow (Passer domesticus) showed a malaria prevalence that was less than 10% before 1990 when worldwide temperatures were cooler, but in recent years nearly 30% were infected. The great tit (Parus major) presented a similarly worrying increase, with less than 3% infected with malaria before 1995 but closer to 15% in recent studies. The blackcap (Sylvia atricapilla), a migrant bird common in Europe that breeds in gardens, once had virtually no avian malaria but a study in 1999 showed nearly 4% had the disease.
　　噶母赛棘博士的论文发表在《全球变化生物学》杂志上，他发现，家雀（Passer domesticus）的疟疾患病率在1990年以前不到10%，那时全球气候比较凉爽， 但是在最近的一些年里几乎30%被感染。 大山雀(Parus major)的患病率有类似令人担忧的增加，1995年之前不到3%，而最近接近15%。 黑头莺在欧洲一种常见的候鸟，它们生活在很多公园里，实际上它们曾经并没有禽疟感染，但是1999年的一项研究显示，几乎4%的黑头莺感染了这种疾病。
　　The effects of warming on avian malaria were not universal. Birds in Asia, North America and South America suffered much less change in their levels of infection during warm years than did birds dwelling 5 in Africa and Europe. Such trends may not have any relevance 6 to the malaria parasites that infect humans. But avian malaria is already ravaging 7 the native birds of Hawaii and it is now wreaking 8 havoc 9 in New Zealand, says Dr Garamszegi. Human beings may be able to mitigate 10 the spread of malaria, but birds will need the help of conservationists if some species are to survive.
　　气候变暖对禽疟的影响并不普遍。 亚洲、北美和南美的鸟类，在气候变暖的若干年里，其感染率的变化较小，而生活在非洲和欧洲的鸟类则受影响较大。 这种趋势与感染人类的疟原虫可能没有任何关系。 但是禽疟已经毁掉了夏威夷的本地鸟类，它目前在新西兰正造成着巨大的破坏，噶母赛棘博士说。 人类也许已经使疟疾的传播减缓，但是如果某些鸟类要幸存下来，就需要环境保护主义者们的帮助。