(单词翻译:单击)
听力文本
Efforts to increase food production in Africa may be increasing the risk of plague infection. Plague has been killing people for hundreds of years. A new report looks at efforts to clear land for farming in natural, undeveloped areas of Tanzania. The report links the development of natural lands into croplands to a sharp increase in the number of rats. It warns the animals often carry insects infected with plague.
Many people become frightened when they hear the word "plague." One of the most famous periods of plague death was known as the "Black Death." It was a time 700 years ago when the disease killed more than 25 million people in Europe.
Health officials do not believe plague will kill many people in Africa. But they are worried about the rising number of plague infections. Thirty to 60 percent of those infected will die if they are not given medicine.
Plague is caused by bacterium. It is passed between animals and humans through the bite of an inflected flea or by touching an infected animal. Rats often carry fleas. The insects feed on the blood of an infected rat.
There are three forms of plague. The most common is bubonic plague. This was the disease that spread in Europe during the 14th century. Bubonic plague causes enlargement of lymph nodes. The lymphatic system is the part of the body's natural defense system against disease.
If the plague infection is not treated, the bacteria can reach the lungs. Then, the person may develop pneumonic plague. This is the least common but most aggressive form of the disease. It can be easily spread through small droplets expelled from the person's nose or mouth. A person infected with bubonic plague cannot infect others.
The World Health Organization says pneumonic plague is one of the most deadly infectious diseases. People suffer high body temperature, shaking, pain, weakness, and muscle and joint pain within two to three days of being infected.
Antibiotic drugs can cure the disease. But the infected individual must take them very quickly, because pneumonic plague can kill people within 24 hours after infection. The WHO says only a small number of reported cases are of the pneumonic form.
Kristofer Helgen is with the Smithsonian Institution's Museum of Natural History in Washington, D.C. He helped to write the new report. It was published online in the American Journal of Tropical Medicine and Hygiene. He spoke to VOA about the disease.
"It maybe surprises people to learn that plague remains a public health concern in various parts of the world -- especially in Africa south of the Sahara. Plague circulates in small mammals and rodents. And when the conditions are right, it's a disease that can spread to people and it can still be a deadly disease. Now, plague is a disease that is treatable with antibiotics. And in that regard, it's considerably maybe less scary, less alarming than other emerging diseases like Ebola. But we should remember that this is a disease that is still on the ground in Africa and remains a public health concern."
Mr. Helgen says the amount of farmland in northern Tanzania has risen sharply in recent years. By his estimate, the croplands have expanded by 70 percent. He and other researchers also attempted to estimate the number of rats in areas where maize was planted. They found the rat population doubled in those areas, compared to neighboring land that had not been developed for agriculture.
Mr. Helgen says that as the amount of farmland increases, so does the number of rats. He notes that the animals and people often live in the same areas, which makes it easier for plague to spread.
"And this is an animal that we often will call a commensal rodent species. And literally that word commensal means ‘eating from the same table' -- in other words, the notion that this is a rat that does go into peoples' houses and villages and interacts with people in their living spaces."
He notes that rats have a major effect on peoples' lives. The animals eat people's food, spread disease and make it more difficult for farmers to succeed.
The plague never completely disappears. It may stay in the wild for 10 or 20 years. Then, something happens and the number of rats increases. The disease then begins to spread in agricultural areas, then to towns and cities. Many people in an area may die, but the disease rarely spreads outside a country. Only people within a limited area are infected. When the number of cases begins to decline, scientists will say "the outbreak has been contained."
The World Health Organization says people should not be afraid of the plague. It says scientists have developed modern and effective ways to prevent, treat and cure the ancient disease.
I'm Christopher Jones-Cruise.
词汇解释
1.plague n. 瘟疫；灾祸；麻烦；讨厌的人 vt. 折磨；使苦恼；使得灾祸
A terrible plague hit the whole Europe.
一场可怕的瘟疫袭击了整个欧洲。
2.lymphatic adj. 淋巴的；含淋巴的 n. 淋巴管；淋巴腺
Carcinoma of the oesophagus usually extends by local invasion and lymphatic spread.
食管癌通常通过局部浸透和淋巴扩散而扩展。
3.rodent adj. 啮齿类的；咬的，嚼的；侵蚀性的 n. [脊椎] 啮齿动物
Researchers observed one bird impale a rodent on a cactus.
研究人员观察到一只鸟把一只啮齿动物钉在一棵仙人掌上。
4.antibiotics n. [药] 抗生素；抗生学
Your doctor may prescribe antibiotics.
你的大夫可能会开抗生素。
参考译文
非洲意在增加粮食产量的努力可能会增加鼠疫传染的风险，鼠疫已经危害人类数百年。最近的一项报告考察了坦桑尼亚天然未开发地区清理土地用于耕地的情况，报告认为将天然土地转为耕地与老鼠数量增加有关联，并警告称动物通常携带感染有鼠疫的昆虫。
很多人在听到“鼠疫”一词会很惊恐，最著名鼠疫爆发是“黑死病”，那是在700年前，当时欧洲有超过2500万人死于鼠疫。
卫生官员不认为鼠疫将导致很多非洲人死亡，但他们担心鼠疫感染病例的增加，如果没有药品，30%到60%的感染者将会死亡。
鼠疫是由细菌感染的，通过感染跳蚤或接触感染动物而在人和动物之间传播。老鼠身上通常有跳蚤，这种昆虫能吸食感染老鼠的血。
鼠疫有三种类型，最常见的是腺鼠疫，这是14世纪传播在欧洲的疾病。腺鼠疫能导致淋巴结肿大，淋巴系统是人体对付疾病的天然防御系统。
如果对鼠疫感染不做治疗，细菌就能抵达肺部，患者就会染上肺鼠疫，这种疾病最少见，但却是危害大的鼠疫类型。可以很容易通过患者鼻子或嘴巴流出的小液滴来传播，而腺鼠疫感染者无法传播给他人。
世界卫生组织称肺鼠疫是最致命的感染疾病之一，患者会在感染两到三天内出现高烧、寒战、疼痛、虚弱、肌肉和关节疼痛。
抗生素可以治愈这种疾病，但感染患者必须立即服药，因为肺鼠疫能在感染的24小时内致人死亡。世卫组织称报告的病例中只有少数是肺鼠疫。
克里斯多佛·赫尔根就职于史密森学会的华盛顿自然博物馆，他参与撰写了这份报告，报告发表在《美国热带医学和卫生杂志》上，他向美国之音谈到这种疾病。
“鼠疫仍是世界上很多地区的公共健康问题，尤其是在撒哈拉南部非洲，这可能会让人们惊讶。鼠疫在小型哺乳动物和啮齿动物之间传播，在条件适当时会传播给人，而且仍是一种致命疾病。现在，可以用抗生素来治疗鼠疫。从这一点来说，鼠疫就没那么可怕了，远不如埃博拉等其他新兴疾病那么可怕。但我们必须记住的是，这种疾病在非洲仍存在，仍然是一个公共健康问题。”
赫尔根说最近几年坦桑尼亚南部的农田数量骤增，据他估计，农田数量增加了70%。他和其他研究者还试图估计种玉米地区老鼠的数量，发现与邻近那些没有开发成农田的地区，这些地区老鼠数量翻倍。
赫尔根说随着农田数量的增加，老鼠的数量也在增加。他指出，动物和人通常生活在同一个地区，使得鼠疫的传播更加容易。
“我们通常称这种动物为共生啮齿类动物，共生的字面意思就是‘在一个饭桌上吃饭’，也就是说，老鼠会进入人的房屋和村庄，侵入人的生活空间。”
他指出，老鼠对人的生活会产生重大影响，这种动物能吃人的食物，传播疾病，还使得农民难以获得好收成。
鼠疫从未彻底消亡，可以还要在野外存在10到20年。然后，发生一些事后，老鼠数量增加，这种疾病开始在农业地区开始传播，然后到达城镇和城市。一个地区的很多人可能会死亡，但这种疾病很少在一个国家之外传播。只有特定区域的人会感染上，当病例数量开始减少时，科学家会说“这种疫情已经得到遏制”。
世卫组织称人们不该害怕鼠疫，称科学家已经研制出现代的有效方法来预防、治疗和治愈这种动物传播疾病。
我是克里斯多夫·琼斯·克鲁斯。
译文为可可英语翻译，未经授权请勿转载！
