The facts about Ebola

(CNN) -- The deadliest outbreak of Ebola virus on record has sparked fears that the killer virus could spread from West Africa to other regions and continents.

The outbreak began with just a handful of cases in Guinea in March. Since then, that number has grown to 909 confirmed cases and another 414 probable or suspected in that country, Sierra Leone and Liberia and Nigeria, according to the World Health Organization.

Some 729 people of the 1,323 total confirmed and possible infections have died, reports WHO as of July 27.

The WHO says "drastic action is needed" to contain Ebola, warning that previously undetected chains of transmission are boosting the numbers of sick and increasing the chances that the disease spreads from Africa.

"This epidemic is without precedent," said Bart Janssens, director of operations for Médecins Sans Frontières, also known as Doctors Without Borders. "It's absolutely not under control, and the situation keeps worsening. ... There are many places where people are infected but we don't know about it."

What's the latest?

The Ebola outbreak has been centered in Guinea, Sierra Leone and Liberia, where authorities have been working to contain the virus.

Photos: Ebola outbreak in West Africa

 

Ebola outbreak kills an American

 

Fighting Ebola on the front lines

 

American doctor battling Ebola

In Liberia, President Ellen Johnson Sirleaf announced Wednesday that, "without exceptions, all schools are ordered closed pending further directive from the Ministry of Education." She also declared Friday a nonworking day "to be used for the disinfection and chlorination of all public facilities."

On the same day, the Peace Corps said it was temporarily removing its 340 volunteers from Liberia, Sierra Leone and Guinea due to the outbreak.

The announcement comes as two Peace Corps volunteers were isolated after coming in contact with someone who ended up dying of Ebola, a spokeswoman for the group said. She said these two Americans "are not symptomatic," and the Peace Corps will work to return them to the United States once they get medical clearance to travel.

Concerns about Ebola aren't confined to those three countries.

Last week, a Liberian government official who had contracted the virus died in isolation at a hospital in Lagos, Nigeria.

Patrick Sawyer, a naturalized American citizen who worked in Liberia, flew to Nigeria intending to attend a conference. After exhibiting symptoms upon arrival July 20, he was hospitalized and died on July 25. He's the first American to die in the outbreak, though two other U.S. aid workers in Liberia have contracted Ebola and are being treated.

Sawyer's was the only known case in Nigeria, WHO said.

And the British government convened an emergency meeting to discuss the threat of Ebola to the UK, even though no case has been reported there. Officials discussed what measures could be taken if UK nationals in West Africa should become infected, Foreign Secretary Philip Hammond said.

Why was someone infected with Ebola allowed on a plane?

Map: The Ebola outbreak

It is unknown whether Sawyer was displaying symptoms before he flew from Monrovia, Liberia's capital, to Ghana and then to Togo to switch planes to fly to Lagos.

His Minnesota-based widow, Decontee Sawyer, told CNN that he had cared for his ill sister in Liberia, though she said he didn't know at the time that his sister had Ebola. When he arrived in Nigeria, he told officials that he had no direct contact with anyone who had the disease.

Because it takes between two and 21 days before Ebola symptoms to show, there's little health officials can do to stop an asymptomatic person from flying to another country, said CNN Chief Medical Correspondent Sanjay Gupta.

So, serious viruses such as Ebola may be just "a plane ride away" from reaching the developed world, according to Marty Cetron of the U.S. Centers for Disease Control and Prevention (CDC).

Mindful of this, Nigeria-based airline companies ASKY and Arik Airsuspended operations at the end of July into Monrovia and Freetown, the capitals of Liberia and Sierra Leone, respectively. ASKY said passengers departing from Conakry, Guinea, would be screened for signs of the virus.

Cetron says it is unlikely the virus would spread on an airplane unless a passenger were to come into contact with a sick person's bodily fluids.

Stressing the key role that those working at airports play in keeping Ebola in check, the CDC spokesman said: "Being educated, knowing the symptoms, recognizing what to do, having a response to protocol, knowing who to call -- those are really, really important parts of the global containment strategies to deal with threats like this."

What else is being done to stop the spread of the disease?

Ebola patients are being isolated by health officials in West Africa, and those who have come into contact with them are being told to monitor their temperatures.

President Sirleaf has closed most of Liberia's borders with neighboring countries, and the few points of entry that are still open will have Ebola testing centers. The President also placed restrictions on public gatherings and ordered hotels, restaurants and other entertainment venues to play a five-minute video on Ebola safety.

The CDC has issued an alert to health workers in the United States to watch out for any patients who may have recently traveled to West Africa and could have contracted the virus.

Why does Ebola generate such fear?

Medecins Sans Frontieres (MSF) describes Ebola as "one of the world's most deadly diseases."

"It is a highly infectious virus that can kill up to 90% of the people who catch it, causing terror among infected communities," it says. The death rate in this outbreak has dropped to roughly 55% because of early treatment.

There is also no vaccination against it.

Of Ebola's five subtypes, the Zaire strain -- the first to be identified -- is considered the most deadly.

The WHO said preliminary tests on the Ebola virus in Guinea in March suggested that the outbreak there was this strain, though that has not been confirmed.

 

Tracking the Ebola virus in Nigeria

 

Ebola scientist: 'It's spectacular'

 

Ebola epidemic 'out of control'

 

Fighting Ebola in urban Africa

What is Ebola, and what are its symptoms?

The Ebola virus causes viral hemorrhagic fever, whichaccording to the U.S. Centers for Disease Control and Prevention (CDC), refers to a group of viruses that affect multiple organ systems in the body and are often accompanied by bleeding.

The virus is named after the Ebola River in the Democratic Republic of Congo (formerly Zaire), where one of the first outbreaks occurred in 1976.

Early symptoms include sudden onset of fever, weakness, muscle pain, headaches and a sore throat. These symptoms can appear two to 21 days after infection.

The WHO says these nonspecific early symptoms can be mistaken for signs of diseases such as malaria, typhoid fever, meningitis or even the plague.

MSF says some patients may also develop a rash, red eyes, hiccups, chest pains and difficulty breathing and swallowing.

The early symptoms progress to vomiting, diarrhea, impaired kidney and liver function and sometimes internal and external bleeding.

Ebola can only be definitively confirmed by five different laboratory tests.

How is it treated?

There are no specific treatments for Ebola. MSF says patients are isolated and then supported by health care workers.

"This consists of hydrating the patient, maintaining their oxygen status and blood pressure and treating them for any complicating infections," it says.

There have been cases of healthcare workers contracting the virus from patients, and the WHO has issued guidance for dealing with confirmed or suspected cases of the virus.

Carers are advised to wear impermeable gowns and gloves and to wear facial protection such as goggles or a medical mask to prevent splashes to the nose, mouth and eyes.

MSF says it contained a 2012 outbreak in Uganda by placing a control area around its treatment center. An outbreak is considered over once 42 days -- double the incubation period of the disease -- have passed without any new cases.

How does it spread?

The WHO says it is believed that fruit bats may be the natural host of the Ebola virus in Africa, passing on the virus to other animals.

Humans contract Ebola through contact with the bodily fluids of infected animals or the bodily fluids of infected humans.

MSF says that while the virus is believed to be able to survive for some days in liquid outside an infected organism, chlorine disinfection, heat, direct sunlight, soaps and detergents can kill it.

MSF epidemiologist Kamiliny Kalahne said outbreaks usually spread in areas where hospitals have poor infection control and limited access to resources such as running water.

"People who become sick with it almost always know how they got sick: because they looked after someone in their family who was very sick -- who had diarrhea, vomiting and bleeding -- or because they were health staff who had a lot of contact with a sick patient," she said.

埃博拉病毒的致命爆發：你需要知道什麼
由蘇珊娜Cullinane和尼克·湯普森，美國有線電視新聞網
2014年7月31日 - 更新1420 GMT（2220 HKT）
觀看此視頻
關於埃博拉病毒的事實
故事突出
新：有1300多名確診和疑似埃博拉出血熱病例，數百人死亡
利比里亞將關閉所有學校，設置“的所有公共設施的消毒......”一天
“這種流行病是沒有先例，”人道主義官員稱
埃博拉出血熱是一種病毒性出血熱，影響多個器官和伴有出血
（CNN） -埃博拉病毒的紀錄最致命的爆發引發了人們的擔憂，兇手病毒可能來自西非蔓延到其他地區和大陸。
爆發開始只是少數的個案在幾內亞三月。從那時起，這個數字已經增長到 909例確診病例，另有414起疑似在該國，塞拉利昂和利比里亞和尼日利亞，根據世界衛生組織。
有的 729人1323總證實和可能的感染已經死亡，世衛組織報告顯示截至7月27日。
世衛組織說，“激烈的行動是必要的”遏制埃博拉，並警告說傳播以前未被發現鏈助推患病的人數，增加了病從非洲傳播的機會。
“這種流行病是沒有先例的，”巴特·詹森，操作的無國界醫生組織，也被​​稱為無國界醫生組織主任。“這是絕對沒有得到控制，而且情況不斷惡化。...有那裡的人都感染了，但我們不知道它很多地方。”

有什麼最新消息？
埃博拉疫情已集中在幾內亞，塞拉利昂和利比里亞，政府一直在努力遏制這種病毒。
組圖：埃博拉疫情在西非 組圖：埃博拉疫情在西非
埃博拉疫情殺死美國人 在前線戰鬥的埃博拉病毒 美國醫生對抗埃博拉病毒
在利比里亞總統埃倫·約翰遜·瑟利夫週三宣布，“沒有例外，所有的學校都下令關閉以待教育部進一步指示。” 她還宣布星期五“用於所有公共設施的消毒和氯化法。”非工作日
就在同一天，和平隊說，這是暫時因爆發取掉來自利比里亞，塞拉利昂和幾內亞的340名志願者。
這一消息來自兩個和平隊志願者進來的人誰最終死於埃博拉病毒接觸後分離，發言人小組表示。她說，這兩個美國人“不對症”，並和平隊會工作，一旦他們獲得體檢合格證明前往他們返回美國。
關於埃博拉病毒的擔憂並不局限於這三個國家。
上週，利比里亞政府官員誰曾感染病毒隔離在尼日利亞拉各斯的一家醫院去世。
帕特里克·索耶，誰在利比里亞工作了歸化的美國公民，飛往尼日利亞擬出席會議。抵達時表現出的症狀7月20日之後，他住院和死亡的7月25日，他是第一個在美國爆發死，但其他兩個美國援助人員在利比里亞染上埃博拉病毒和正在接受治療。
索耶的是尼日利亞的唯一已知的情況下，他說。
和英國政府召開緊急會議，討論埃博拉英國的威脅，即使沒有案件被報導存在。官員討論了哪些措施，如果在西非英國國民應成為感染可採取外交大臣菲利普·哈蒙德說。
為什麼有人感染了埃博拉允許在飛機上？
圖：埃博拉疫情圖：埃博拉疫情
它是未知的索耶是否顯示症狀之前，他從蒙羅維亞，利比里亞首都飛過，加納，然後多哥轉飛機飛往拉各斯。
他位於明尼蘇達州的寡婦，Decontee索耶告訴CNN說，他已經照顧他生病的妹妹在利比里亞，但她說自己並不知道，他的妹妹有埃博拉病毒的時間。當他在尼日利亞趕到，他告訴官員，他曾與人誰得了這個病沒有直接的聯繫。
因為它需要之前，埃博拉病毒的症狀2至21天之間，顯示，幾乎沒有衛生官員無法阻止無症狀的人，從飛行到另一個國家，美國有線電視新聞網說，首席醫學記者桑賈伊·古普塔。
因此，嚴重的病毒，例如埃博拉病毒可能只是“飛機車程”到達發達國家，根據美國疾病控制和預防的馬蒂·塞特龍（CDC）。
念及此，尼日利亞為基地的航空公司公司ASKY和阿里克航空在七月底到蒙羅維亞和弗里敦，利比里亞和塞拉利昂，分別為首都暫停運營。ASKY說，乘客從科納克里，幾內亞出發，將進行篩選，病毒的跡象。
塞特龍說，這是不太可能的病毒傳播會在飛機上，除非有乘客要接觸到生病的人的體液接觸。
他強調，那些在機場工作的埃博拉保持在檢查起到的關鍵作用，疾病預防控制中心的發言人說：“受教育，知道了症狀，認識該怎麼做，不必協議的回應，知道給誰打電話 - 這些都是真的，全球圍堵戰略的非常重要的部分來處理這樣的威脅。“
什麼ELS ë 正在做阻止疾病的蔓延？
埃博拉患者被隔離在西部非洲的衛生官員，和那些誰已經進入與他們接觸被告知監控其溫度。
瑟利夫總統已關閉大部分利比里亞邊界與周邊國家，以及一些進入 ​​點仍然打開將有埃博拉病毒測試中心。總統還放在公眾集會，並責令賓館，飯店等娛樂場所限制埃博拉安全發揮了五分鐘的視頻。
疾病預防控制中心已發出警報，衛生工作者在美國看出來誰可能最近去過西非，可能染上病毒的任何患者。
為什麼埃博拉病毒產生這種恐懼？
無國界醫生組織（MSF）描述埃博拉病毒為“世界上最致命的疾病之一。”
“這是一種傳染性很強的病毒，可以殺死高達90％誰抓住它，造成感染社區中製造恐怖的人，”它說。因為早期治療的死亡率在這種爆發已經下降到大約55％。
也有反對沒有接種疫苗。
埃博拉病毒的五個亞型，扎伊爾毒株 - 第一個被確定的 - 被認為是最致命的。
世衛組織說，在埃博拉病毒在幾內亞在三月份的初步測試表明，該疫情有這樣的壓力，雖然這還沒有得到證實。
追踪埃博拉病毒在尼日利亞 埃博拉科學家：“這是壯觀' 埃博拉疫情“失控” 在城市作戰非洲埃博拉病毒
什麼是埃博拉病毒，什麼是它的症狀？
埃博拉病毒導致病毒性出血熱，而根據美國疾病控制和預防中心（CDC）的，指的是一組累及多個器官系統在體內，往往伴有出血病毒。
埃博拉河後，該病毒被命名為剛果民主共和國（前扎伊爾），其中第一個爆發的一次發生在1976年。
早期症狀包括突然發燒，無力，肌肉疼痛，頭痛和喉嚨痛。這些症狀可以感染後會出現2〜21天。
世衛組織說，這些非特異性的早期症狀可被誤認為是疾病的徵兆，如瘧疾，傷寒，腦膜炎，甚至瘟疫。
無國界醫生表示，部分患者也可出現皮疹，眼睛發紅，打嗝，胸痛和呼吸困難和吞嚥。
早期症狀發展為嘔吐，腹瀉，損害腎臟和肝臟功能，有時內部和外部出血。
埃博拉只能由五個不同的實驗室測試來明確證實。
如何治療？
有沒有針對埃博拉病毒的具體治療方法。無國界醫生表示，病人被隔離，然後由醫護人員的支持。
“這包括保濕病人，保持其氧狀態和血壓和治療它們用於任何複雜的感染，”它說。
已經有醫護人員案件，從患者感染病毒，而世界衛生組織已發出處理病毒的確診或疑似病例的指導。
照顧者宜戴不透水的禮服和手套，穿防護面部，如護目鏡或外科口罩，以防止飛濺的鼻子，嘴巴和眼睛。
無國界醫生表示，它包含了2012爆發在烏干達放置一個控制區域圍繞其治療中心。爆發時一度被認為超過42天 - 加倍疾病的潛伏期 - 未進行任何新的病例。
它是怎樣傳播的？
世界衛生組織說，據信，果蝠可能是埃博拉病毒在非洲的自然宿主，通過對病毒傳播給其他動物。
人類合同埃博拉通過與受感染的動物的體液或感染人的體液接觸。
無國界醫生表示，雖然該病毒被認為是能夠在液體中存活數天被感染的生物，氯消毒，高溫，陽光直射，肥皂外和清潔劑可以殺死它。
無國界醫生流行病學Kamiliny Kalahne說爆發通常散佈在醫院有窮感染控制和有限的訪問，如自來水資源的地區。
“誰生病了它的人幾乎都知道他們是怎麼生病了：因為他們看起來有人在他們的家庭誰是病得很重之後 - 誰了腹瀉，嘔吐和出血 - 或者因為他們是醫務人員誰有很多接觸有一個生病的病人，“她說。