首页
登录
职称英语
Researchers who picked up and analyzed wild chimp droppings said on Thursday
Researchers who picked up and analyzed wild chimp droppings said on Thursday
游客
2024-12-16
30
管理
问题
Researchers who picked up and analyzed wild chimp droppings said on Thursday they had shown how the AIDS virus originated in wild apes in Cameroon and then spread in humans across Africa and eventually the world. Their study, published in the journal Science, supports other studies that suggest people somehow caught the deadly human immunodeficiency virus (HIV) from chimpanzees, perhaps by killing and eating them.
"It says that the chimpanzee group that gave rise to HIV... this chimp community resides in Cameroon," said Beatrice Hahn of the University of Alabama, who led the study. "But that doesn’t mean the epidemic originated there because it didn’t," Hahn, who has been studying the genetic origin of HIV for years, said in a telephone interview.
"We actually know where the epidemic took off. The epidemic took off in Kinshasa, in Brazzaville." Kinshasa is in the Democratic Republic Congo, formerly Zaire, and faces Brazzaville, in Congo, across the Congo River. Studies have traced HIV to a man who gave a blood sample in 1959 in Kinshasa, then called Leopoldville. Later analysis found the AIDS virus.
In people, HIV leads to AIDS but chimps have a version called simian immune deficiency virus (SIV) that causes them no harm. Humans are the only animals naturally susceptible to HTV. AIDS was only identified 25 years ago. The virus now infects 40 million people around the world and has killed 25 million. Spread in blood, sexual contact and from mother to child during birth or breastfeeding, HTV has no cure and there is no vaccine, although drug cocktails can control it.
And like so many new infections, AIDS appears to have been passed to humans from animals they slaughtered. SIV has been found in captive chimps but Hahn wanted to show it could be found in the wild too. Her international team got the cooperation of the government in Cameroon and they hired skilled trackers.
"The chimps in that area are hunted. It’s certainly impossible to see them. It is hard to track them and find these materials," she said. But the trackers managed to collect 599 samples of droppings. Hahn’s lab found DNA, identified each individual chimp and then found evidence of the virus.
"We went to 10 field sites and we found evidence of infection in five. We were able to identify a total of 16 infected chimps and we were able to get viral sequences from all of them," Hahn said. Up to 35 percent of the apes in some communities were infected. Not only that, they could find different varieties, called clades, of the virus.
"We found some of the clades were really, really very closely related to the human virus and others were not," she said. Chimps separated by a river were infected with different clades, Hahn said. And a river may have carried the virus into the human population. "So how do you get from southern Cameroon to the Democratic Republic of Congo?" Hahn asked. "Some human must have done so. There is a river that goes from that southeastern comer of Cameroon down to the Congo River."
Ivory and hardwood traders used the Sangha River in the 1930s, when the original human-to-human transmission is believed to have happened. Hahn’s study suggests the virus passed from chimpanzees to people more than once. "We don’t really know how these transmissions occurred," Hahn said.
"We know that you don’t get it petting a chimp, or from a toilet seat, just like you can’t get HTV from a toilet seat. It requires exposure to infected blood and infected body fluids. So if you get bitten by an angry chimp while you are hunting it, which could do it."
Hahn’s study only applies the HTV group M, which is the main strain of the virus responsible for the AIDS pandemic. "It’s quite possible that still other (chimpanzee SIV) lineages exist that could pose risks for human infection and prove problematic for HTV diagnostic and vaccines," her team wrote. [br] From the description in the passage, we learn that
选项
A、monkeys are also susceptible to HTV.
B、AIDS has killed 25 million people in the last 25 years.
C、vaccine has been developed to prevent AIDS.
D、AIDS can be cured by drug cocktails.
答案
B
解析
从第4段第3句和第4句可得知B与其对应,为正确答案。
转载请注明原文地址:https://tihaiku.com/zcyy/3877061.html
相关试题推荐
ResearcherswhopickedupandanalyzedwildchimpdroppingssaidonThursday
ResearcherswhopickedupandanalyzedwildchimpdroppingssaidonThursday
ResearcherswhopickedupandanalyzedwildchimpdroppingssaidonThursday
ResearcherswhopickedupandanalyzedwildchimpdroppingssaidonThursday
Researcherssaylightexercisemayhelpto[originaltext]Lightexerciseduri
Ateamofinternationalresearchershasfoundnewevidencethatanendangered
Ateamofinternationalresearchershasfoundnewevidencethatanendangered
Ateamofinternationalresearchershasfoundnewevidencethatanendangered
Losingweightiseasierwhenthereismoneyontheline,U.S.researcherss
Losingweightiseasierwhenthereismoneyontheline,U.S.researcherss
随机试题
What’stheprobablerelationshipbetweenthetwospeakers?[originaltext]M:Excu
国家助学金用于资助高校全日制本专科(不含高职)在校生中的家庭经济困难学生的生活费
本项目参建各方的人员可以专家身份参加专家论证会。()
下列关于社会审计人员对委托单位责任的表述中,错误的是:A.审计人员应当按时按质完
在运行中的电流互感器二次回路上工作时,()是正确的。 (A)用铅丝将二次短
()是企业不断优化供应商队伍、强化供应链质量优势的有效手段。 A.针对供应商
(2021年7月真题)期货从业人员涉嫌违法违规需要给予行政处罚的,中国期货业协会
会计科目的性质决定了账户的性质,会计科目的分类决定了账户的分类。()
对带电抗器的6~1OkV出线回路,按电抗器前短路计算的设备为()。 A.6~1
肺炎并发脓胸的常见病原体A.溶血性链球菌 B.大肠杆菌 C.肺炎球菌 D.
最新回复
(
0
)