What we know (and don't know) about Ebola - Alex Gendler

翻译人员: Jenny Yang 校对人员: Yuanqing Edberg

In the summer of 1976,

在1976年夏天

a mysterious epidemic suddenly struck two central African towns,

两个中非小镇上爆发了场奇怪的流行病

killing the majority of its victims.

导致大多数病人死亡

Medical researchers suspected

医学家曾怀疑

the deadly Marburg virus to be the culprit.

高危的马尔堡病毒是元凶

But what they saw in microscope images was an entirely new pathogen,

但通过显微镜 他们发现了一种新的病原

which would be named after the nearby Ebola river.

它因附近的埃博拉河而得名

Like yellow fever or dengue,

就像黄热病和登革热

the disease caused by the Ebola virus is a severe type of hemorrhagic fever.

由埃博拉病毒引起的疾病 是一种严重的出血性发热。

It begins by attacking the immune system's cells

病毒首先攻击免疫系统

and neutralizing its responses,

来减弱免疫反应

allowing the virus to proliferate.

使自身繁殖

Starting anywhere from two to twenty days after contraction,

被感染后的二到二十天后，

initial symptoms like high temperature,

最初的症状出现包括高热，

aching,

身体疼痛，

and sore throat

以及喉咙痛

resemble those of a typical flu,

这与典型流感相似，

but quickly escalate to vomiting,

但症状迅速加剧至呕吐，

rashes,

红疹

and diarrhea.

和腹泻。

And as the virus spreads,

病毒扩散时

it invades the lymph nodes and vital organs,

它入侵淋巴结和重要器官，

such as kidneys and liver, causing them to lose function.

比如肝和肾， 使其功能衰竭。

But the virus itself is not what kills Ebola victims.

但病毒本身并不是致死原因。

Instead, the mounting cell deaths trigger an immune system overload,

大量细胞死亡所导致的免疫系统超负荷运转，

known as a cytokine storm,

也就是”细胞因子风暴“，

an explosion of immune responses that damages blood vessels,

过度的免疫反应破坏了血管，

causing both internal and external bleeding.

导致了内出血和外出血

The excessive fluid loss and resulting complications

过度的体液流失和并发症

can be fatal within six to sixteen days of the first symptoms,

在症状出现的头六到十六天会是致命的，

though proper care and rehydration therapy

恰当的治疗和补水

can significantly reduce mortality rates in patients.

能显著减少病人的死亡率。

Fortunately, while Ebola is highly virulent,

幸好，虽然埃博拉极度致命

several factors limit its contagiousness.

它的传染性被以下因素所限制

Unlike viruses that proliferate through small, airborne particles,

与其它的病毒不同

Ebola only exists in bodily fluids,

埃博拉仅存于体液中

such as saliva,

比如唾液

blood,

血液

mucus,

粘膜

vomit,

or feces.

呕吐物

或粪便中

In order to spread,

埃博拉的传播

these must be transmitted from an infected person into another's body

只能通过病患与健康人之间

through passageways such as the eyes, mouth, or nose.

眼，嘴，或鼻的接触。

And because the disease's severity

由于疾病的严重性

increases directly along with the viral load,

随着病毒数目的增长而增长，

even an infected person is unlikely to be contagious

即使是被感染的患者也可能没有传染性

until they have begun to show symptoms.

直到有症状产生。

While Ebola has been shown to survive on surfaces for several hours,

因为埃博拉可以在物体表面生存数小时，

and transmission through sneezing or coughing is theoretically possible,

而且疾病理论上可以通过喷嚏和咳嗽传播，

virtually all known cases of contraction have been through direct contact

几乎所有已知病例都是由于

with the severely ill,

接触严重病患而感染，

with the greatest risk posed to medical workers

所以医务人员

and friends or relatives of the victims.

病人的亲友都属于高危人群。

This is why, despite its horrifying effects,

这也是为什么尽管埃博拉很致命，

Ebola has been far less deadly overall than more common infections,

至今，它的致死人数还不及一些常见的感染，

such as measles,

比如麻疹，

malaria,

疟疾，

or even influenza.

和流感，

Once an outbreak has been contained,

一旦疫情得到控制，

the virus does not exist in the human population

病毒不会存在于人群中

until the next outbreak begins.

直到它下一次爆发。

But while this is undoubtedly a good thing,

虽然这肯定是件好事

it also makes Ebola difficult to study.

但也使埃博拉难以被研究

Scientists believe fruit bats to be its natural carriers,

科学家认为果蝠是病毒的携带者

but just how it is transmitted to humans remains unknown.

但它们也不知道病毒是如何传染给人类的

Furthermore, many of the countries where Ebola outbreaks occur

另外，许多爆发埃博拉的国家

suffer from poor infrastructure and sanitation,

都缺乏良好的基础和卫生设施，

which enables the disease to spread.

这也导致了疾病的蔓延。

And the poverty of these regions,

同时，由于这些地区较为贫穷，

combined with the relatively low amount of overall cases

加上偏少的患病人数

means there is little economic incentive for drug companies to invest in research.

所以药企无法得到较高利润 也限制了对埃博拉的研究

Though some experimental medicines have shown promise,

虽然有些药物已崭露头角，

and governments are funding development of a vaccine,

并且政府也在支持发展疫苗，

as of 2014,

但就2014年来说，

the only widespread and effective solutions to an Ebola outbreak remain

唯一能有效应对埃博拉爆发的措施是

isolation,

隔离病患，

sanitation,

卫生措施，

and information.

和信息公开。