【题目】 Humans have been battling viruses since before we had even evolved into our modern form, but we’re a long way from winning the fight against them. Here are a few of the worst killers.
Marburg virus
Scientists identified Marburg virus in 1967, when small outbreaks occurred among lab workers in Germany who were exposed to infected monkeys. The infected people develop high fevers and bleeding throughout the body. Marburg can be passed on from human to human via direct contact. The death rate is 80%in the 1998-2000 outbreak in Congo and in the 2005 outbreak in Angola.
Ebola virus
The first known Ebola outbreaks in humans struck Africa in Sudan and Congo in 1976. The natural host of Ebola is bats. The virus is spread through contact with infected people or animals. Symptoms include fever, bleeding and organ failure. The death rate is 50%to 70%.
Hantavirus
Hantavirus was first recognized as an infectious disease in the 1950s in Korea. But it first gained wide attention in the U. S. in 1993, when a healthy young man and his fiancee died within days of developing shortness of breath. Hantavirus was isolated from a deer mouse. More than 600 people in the U. S. are now infected and 36%have died. The virus doesn’t spread from human to human.
Mers-CoV virus
Mers-CoV virus had an outbreak in Asia, Saudi Arabia in 2012 and South Korea in 2015. The virus likely originated in bats. The disease infected camels before passing into humans and causes fever and shortness of breath. It has a death rate between 30%and 40%, making it the most deadly of the known coronavirus (冠状病毒) family. Mers-CoV spreads from one person to another.
【1】Which virus caused the highest death rate in a particular area?
A.Marburg virus.B.Ebola virus.
C.Hantavirus.D.Mers-CoV virus.
【2】What can we know about Hantavirus?
A.It is a type of coronaviruses.B.It was identified in the 21st century.
C.It was first found in the United States.D.It only spreads from animals to humans.
【3】In what sense are Ebola virus and Mers-CoV virus similar?
A.They may have the same host.B.They originate in the same continent.
C.They belong to the same virus family.D.They have exactly the same symptoms.
在线课程【答案】
【1】A
【2】D
【3】A
【解析】
这是一篇说明文。在我们进化成现代形态之前，人类就已经在与病毒战斗了，但我们距离赢得与病毒的战斗还有很长的路要走。文章主要介绍了四种最可怕的病毒种类。
【1】
细节理解题。根据第二段中The death rate is 80%in the 1998-2000 outbreak in Congo and in the 2005 outbreak in Angola.可知1998年到2000年刚果暴发和2005年安哥拉暴发的马尔堡病毒的死亡率为80%。由此可知，Marburg病毒在某一特定地区造成的死亡率最高。故选A。
【2】
细节理解题。根据倒数第二段中. But it first gained wide attention in the U. S. in 1993, when a healthy young man and his fiancee died within days of developing shortness of breath. Hantavirus was isolated from a deer mouse.The virus doesn’t spread from human to human.可知，但它在1993年首次在美国引起广泛关注，当时一位健康的年轻男子和他的未婚妻因呼吸短促而在几天内去世。从一只鹿鼠中分离出汉坦病毒。病毒不会在人与人之间传播。由此可知，汉坦病毒只从动物传染给人类。故选D。
【3】
细节理解题。根据第三段中The natural host of Ebola is bats.可知埃博拉病毒的天然宿主是蝙蝠。以及最后一段中The virus likely originated in bats.可知该病毒可能起源于蝙蝠。由此可知，埃博拉病毒和中东呼吸综合症病毒的相似之处在于他们可能有同一个宿主。故选A。