VOA慢速英語：研究表明：新登革熱疫苗可能導(dǎo)致嚴(yán)重疾病

A new study shows a vaccine designed to prevent dengue fever could actually be making people sick.
一項新的研究表明，一種旨在預(yù)防登革熱的疫苗實際上可能會使人生病。
Dengue infects an estimated 400 million people worldwide each year. The virus spreads to human beings through the bite of an insect, the mosquito.
預(yù)計全球每年有4億人感染登革熱。這種病毒通過蚊蟲叮咬傳播給人類。
Most people who get dengue suffer health problems like those resulting from a mild case of influenza, like a higher than normal body temperature.
多數(shù)登革熱感染者會出現(xiàn)一些健康問題，像是輕微流感引發(fā)的這些癥狀，像是體溫略高于常。
But the illness is more severe the second time a person gets it. In serious cases, it can cause bleeding inside the body and even death. About 25,000 people a year die from the infection.
但是這種疾病在人們第二次患病時會更加嚴(yán)重。在嚴(yán)重情況下，它會導(dǎo)致體內(nèi)出血甚至死亡。每年大約有2.5萬人死于這種感染。
The drug Dengvaxia is so far the only vaccine approved for use against dengue. Several countries - including Brazil, Mexico, Costa Rica, Paraguay and the Philippines - have already approved use of the drug. But health officials are still trying to decide the best way to release the vaccine.
Dengvaxia是迄今為止唯一批準(zhǔn)用于對抗登革熱的疫苗。包括巴西、墨西哥、哥斯達(dá)黎加、巴拉圭和菲律賓在內(nèi)的幾個國家已經(jīng)批準(zhǔn)了該藥的應(yīng)用。但是衛(wèi)生官員仍在設(shè)法確定釋放該疫苗的最佳途徑。
Trials of Dengvaxia involved more than 30,000 people in 10 countries. Among young people, the drug was found to reduce infections by 60 percent, and hospitalizations by 80 percent. But over time, many of those vaccinated got seriously ill with dengue.
Dengvaxia的試驗涉及了10個國家的3萬多人。在年輕人中，這種藥物被發(fā)現(xiàn)可以降低60%的感染以及80%的住院治療。但是隨著時間推移，許多接種者患上了嚴(yán)重的登革熱疾病。
Researchers from Britain and the United States studied the results of the tests. The researchers were from Johns Hopkins Bloomberg School of Public Health, Imperial College London and the University of Florida. They found that the vaccine acted as a first infection in people who had not had the virus before.
來自英國和美國的研究人員研究了這些試驗結(jié)果。這些研究人員分別來自約翰霍普金斯大學(xué)彭博公共衛(wèi)生學(xué)院、倫敦帝國學(xué)院和佛羅里達(dá)大學(xué)。他們發(fā)現(xiàn)，這種疫苗在此前從未感染病毒的人群中扮演了首次感染的角色。
The researchers reported their findings in the journal Science.
研究人員在《科學(xué)》雜志上發(fā)表了他們的研究結(jié)果。
The researchers say they are concerned that people who get infected a second time after the vaccine can get severely sick. This could explain why young children especially were getting ill. They had not lived long enough to get a first infection.
研究人員表示，他們擔(dān)心人們在接種后被第二次感染會病得非常嚴(yán)重。這就能解釋為什么尤其是小孩開始患病，因為他們年齡不大沒有第一次感染。
Based on the findings, the World Health Organization is warning health care workers not to give the vaccine to anyone younger than nine.
根據(jù)這項研究結(jié)果，世界衛(wèi)生組織提醒醫(yī)護(hù)人員不要給九歲以下兒童接種該疫苗。
But data showed that people other than children were getting severe dengue cases if they had the vaccine, but were not infected before they received it.
但是數(shù)據(jù)顯示，除兒童之外，其他人如果接種了疫苗但是在接種前沒有感染過也開始患上了嚴(yán)重的登革熱病。
"What we suggest is ... maybe having been exposed to dengue in the past is more important than age itself," said Isabel Rodriguez-Barraquer of the Bloomberg school.
彭博公共衛(wèi)生學(xué)院的Isabel Rodriguez-Barraquer表示，“我們想說的是，可能過去感染過登革熱比年齡本身更為重要。”
The study found that the vaccine should not be a problem in countries with many cases of dengue. In such areas, Dengvaxia was found to reduce severe sickness and hospitalizations by 20 percent to 30 percent.
研究發(fā)現(xiàn)，這種疫苗在登革熱病例很多的國家不應(yīng)該算是個問題。在這些地區(qū)，Dengvaxia被發(fā)現(xiàn)減少了20%到30%的嚴(yán)重疾病和住院治療。
But the researchers warned that in countries where only 10 percent of people have been infected with dengue, the vaccine needs to be carefully used. Ideally, Rodriguez-Barraquer said, people should be tested before getting vaccinated, to see if they have been infected in the past.
但是研究人員警告稱，在那些只有10%人口感染登革熱的國家，這種疫苗需要謹(jǐn)慎使用。Rodriguez-Barraquer表示，理想情況下，人們在接種前應(yīng)該檢測是否以前被感染過。
The researchers are also looking forward to trial results from additional new dengue vaccines.
研究人員還在期待著更多新登革熱疫苗的試驗結(jié)果。
I'm Bryan Lynn.
布萊恩·林恩報道。