關注社會:H7N9病毒或可在空氣中高效傳播
A new bird flu virus that has infected 132 people in recent months and killed 43 is capable of spreading from mammal to mammal through the air, a study by a team of Chinese virologists has found, rekindling fears that the virus could eventually pass from person to person.
中國一個病毒學家團隊的研究報告發現，近幾個月感染132人並導致43人死亡的新型禽流感病毒可在哺乳動物之間通過空氣傳播，這再次引發了對於這種病毒最終可能在人際傳播的擔憂。The study, published online Thursday by the journal Science, found that one strain of the H7N9 virus isolated from a human subject in eastern China's Anhui province was 'highly transmissible' between ferrets by respiratory droplets, according to a summary posted to Science's website.
該研究報告上週四發佈在《科學》(Science)雜誌的網站上。據發佈在《科學》雜誌網站上的研究摘要說，研究發現，從中國安徽省一位感染了H7N9禽流感病毒的患者體內分離出來的毒株可在雪貂之間通過飛沫高效傳播。Led by Chen Hualan, one of China's top virologists, researchers tested the ability of multiple strains of the virus to spread by placing three healthy ferrets in one cage next three infected ferrets in another cage. In most cases, only one of the healthy ferrets became infected, but in the case of the Anhui strain, all three of the healthy ferrets became infected with the virus. A repeat of the experiment with the Anhui strain produced the same result.
在中國主要病毒學家陳化蘭的帶領下，研究人員測試了H7N9禽流感病毒多個毒株的傳播能力，方法是將三隻健康的雪貂放在一個籠子裏，旁邊的一個籠子裏放入三隻感染了病毒的雪貂。在大部分情況下，只有一隻健康的雪貂感染了病毒，但對於從安徽患者體內分離出來的毒株，三隻健康雪貂全部感染。用安徽的毒株重複實驗產生的結果相同。
Ferrets respond to flu viruses similarly to humans and thus are often used to test the potential of avian flu viruses in infect and spread between people.
雪貂對流感病毒做出的反應與人類相似，因此常常被用來測試禽流感病毒感染人類及人際傳播的可能。H7N9 was confirmed to have made the jump from birds to humans for the first time in March, when state media revealed that two people in Shanghai had died after being infected with the virus the previous month. Other deaths soon followed, prompting officials to shut down wet markets and slaughter poultry in a number of cities amid fears of a potential epidemic.
今年3月，中國證實H7N9禽流感病毒首次出現禽類向人類傳播的病例，當時中國國有媒體披露說，上海有兩人此前一個月感染了H7N9病毒，之後死亡。很快有其他感染者死亡，由於擔心可能爆發大範圍的疫情，官員們關閉了多個城市的活禽市場，並撲殺了大量禽鳥。Despite discovering a handful of 'family clusters' or infections of multiple family members health authorities have yet to turn up evidence that H7N9 is capable human-to-human transmission, which would make it far more dangerous.
儘管發現有一些“家庭集羣式”感染（即多個家庭成員感染）的情況，但衛生主管部門尚未找到證據證明H7N9能夠發生人與人之間的傳播。如果出現人際傳播，這種病毒的危險性就大得多。But the new study reinforces earlier warnings from the World Heath Organization and Chinese authorities that the virus has a higher potential for human-to-human transmission than any other known bird-flu virus.
但上述新的研究印證了早些時候世界衛生組織(World Health Organization)和中國有關部門發出的警告，他們曾警告說，相比其他任何一種已知的禽流感病毒，H7N9病毒有更高的人際傳播的可能。'The findings suggest that only a few amino acid changes would be needed to make the avian H7N9 viruses highly transmissible,' the official Xinhua news agency quoted Ms. Chen as saying on Friday.
新華社上週五援引陳化蘭的話說，研究結果表明，H7N9病毒株可能只需要幾個氨基酸的突變，就會具有高度傳播性。In its summary of the new study, Science notes that the results conflict with an earlier study by the U.S. Centers for Disease Control featuring a similar experiment using the same Anhui strain of the virus. In that experiment the virus spread to only two of six healthy ferrets, leading researchers to conclude that the virus did not spread readily through the air.
在對上述新的研究的總結中，《科學》雜誌指出，研究結果與早些時候美國疾病控制與預防中心(U.S. Centers for Disease Control and Prevention)使用同樣的安徽毒株進行的類似研究得出的結果不一致。在美國疾病控制與預防中心的實驗中，病毒只傳染給了六隻健康雪貂中的兩隻，研究人員由此得出結論，病毒不易通過空氣傳播。A third study led by virologist Yoshihiro Kawaoka produced similar results to the CDC. The researchers concluded nevertheless that H7N9 respresented a significant public health threat.
另外一項由病毒學家河岡義裕(Yoshihiro Kawaoka)主持的研究得出的結果與美國疾病控制與預防中心得出的結果類似。不過研究人員仍得出結論說，H7N9可能給公衆健康帶來嚴重威脅。The number of human H7N9 infections has dropped off significantly in recent months, though Ms. Chen warned in her interview with Xinhua the virus continues to exist in animals. The fact that the virus doesn't produce symptoms in birds means it can 'replicate silently' and transmit to unsuspecting humans, providing multiple chances for it to mutate and potentially become more dangerous, she said.
人感染H7N9禽流感病毒的病例近幾個月大幅減少，不過陳化蘭在接受新華社採訪時警告說，這種病毒仍存在於動物體內。她說，這種病毒在禽類身上並不會出現症狀，這一事實意味着，它可以沉默地複製而不引人注意，這增加了它傳染給人並獲得更多變異成爲致病、傳播能力更強病毒的機會。
