5 things to know about Ebola outbreak in West Africa

At least 729 people have died since cases first emerged in March: 339 in Guinea, 233 in Sierra Leone, 156 in Liberia and one in Nigeria. Two American health workers in Liberia have been infected, and an American man of Liberian descent died in Nigeria from the disease

An Ebola outbreak that has killed more than 700 people in West Africa is moving faster than efforts to control the disease, the head of the World Health Organization warned as presidents from the affected countries met Friday in Guinea's capital.

Dr Margaret Chan, the WHO's director-general, said the meeting in Conakry "must be a turning point" in the battle against Ebola, which is now sickening people in three African capitals for the first time in history.

"If the situation continues to deteriorate, the consequences can be catastrophic in terms of lost lives but also severe socio-economic disruption and a high risk of spread to other countries," she said, as the WHO formally launched a $100 million response plan that includes deploying hundreds more health care workers.

Medecins Sans Frontieres, also known as Doctors Without Borders, said the WHO pledge "needs to translate to immediate and effective action." While the group has deployed some 550 health workers, it said it did not have the resources to expand further.

Read:Ebola moving faster than control efforts, says WHO

"Over the last weeks, there has been a significant surge in the epidemic - the number of cases has increased dramatically in Sierra Leone and Liberia, and the disease has spread to many more villages and towns," the organization said in a statement. "After a lull in new cases in Guinea, there has been a resurgence in infections and deaths in the past week."

At least 729 people have died since cases first emerged in March: 339 in Guinea, 233 in Sierra Leone, 156 in Liberia and one in Nigeria. Two American health workers in Liberia have been infected, and an American man of Liberian descent died in Nigeria from the disease, health authorities there say.

A poster, among those being distributed by UNICEF, bears information and illustrations on the symptoms of Ebola virus disease

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Here are five things to know about Ebola and how it is spread:

1.The West Africa Ebola outbreak is now the largest in history

The current outbreak in Liberia, Guinea and Sierra Leone has sickened more than 1,300 people and killed more than 700 this year.

2. But some people have survived Ebola

While the fatality rate for Ebola can be as high as 90%, health officials in the three countries say people have recovered from the virus and the current death rate is about 70%. Those who fared best sought immediate medical attention and got supportive care to prevent dehydration even though there is no specific treatment for Ebola itself.

3. Ebola can look a lot like other diseases

The early symptoms of an Ebola infection include fever, headache, muscle aches and sore throat, according to the World Health Organization. It can be difficult to distinguish between Ebola and the symptoms of Malaria, Typhoid fever or Cholera. Only in later stages do people with Ebola begin bleeding both internally and externally, often through the nose and ears.

4. Ebola is only spread through bodily fluid

The Ebola virus is not airborne, so people would have to come into contact with the bodily fluids of an infected person. These include blood, sweat, vomit, feces, urine, saliva or semen - making transmission through casual contact in a public setting unlikely.

5. Fear and misinformation though is making things worse

In each of the affected countries, health workers and clinics have come under attack from panicked residents who mistakenly blame foreign doctors and nurses for bringing the virus to remote communities. Family members also have removed sick Ebola patients from hospitals, including one woman in Sierra Leone's capital who later died. Police had to use tear gas to disperse others who attacked a hospital in the country.

In this September 29, 2007, file photo, a 43-year-old Congolese patient, center, who has been confirmed to have Ebola hemorrhagic fever in Kampungu, Kasai Occidental province, Congo.

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