(CNN) — Fear over Ebola is growing as international leaders and health organizations struggle to try to stop the deadly epidemic in West Africa.
The Ebola outbreak “is moving faster than our efforts to control it,” Margaret Chan, director-general of the World Health Organization, said in a statement Friday. “This is an unprecedented outbreak accompanied by unprecedented challenges. And these challenges are extraordinary.”
This is the first Ebola outbreak in West Africa and involves the most deadly strain in the Ebola virus family, Chan said.
“If the situation continues to deteriorate, the consequences can be catastrophic in terms of lost lives but also severe socioeconomic disruption and a high risk of spread to other countries.”
One of those countries could be the United States, health officials have said. In fact, a plane used to transport infected patients is believed to be on its way to pick up two Americans infected with the virus in Liberia and bring them home.
Here’s what you need to know about the Ebola outbreak today:
How many people have died?
As of Sunday, the World Health Organization had confirmed 909 cases and 485 deaths in Guinea, Sierra Leone, Liberia and Nigeria. It suspects that there may have been up to 1,323 cases and 729 deaths.
“The outbreak is by far the largest ever in the nearly four-decade history of this disease,” Chan said. “It is the largest in terms of numbers of cases and deaths. … It is the largest in terms of geographical areas already affected and others at immediate risk of further spread.”
Centers for Disease Control and Prevention Director Tom Frieden said Thursday that it could take three to six months to stop the epidemic.
Why is it spreading so quickly?
First of all, there’s no vaccine for Ebola. So health officials have to stop the infection by isolating patients to prevent further transmission.
Past outbreaks have primarily occurred in rural areas, where people were not frequently traveling and infecting others. This outbreak has made it to several of the region’s major cities, including Freetown, Sierra Leone; Monrovia, Liberia; and Conakry, Guinea.
These cities have international airports, which opens up the possibility of infected patients traveling abroad. For example, American Patrick Sawyer became infected with Ebola in Liberia and traveled via plane to Lagos, Nigeria, where he died. Health officials are still tracing all the people he came in contact with along the way.
Back up. Ebola is coming to the U.S.?
On Thursday, a medical charter plane outfitted with an isolation pod left Cartersville, Georgia, about 5 p.m. The aircraft was scheduled to fly to Monrovia, Liberia, and could return with Dr. Kent Brantly and/or Nancy Writebol, who were infected with Ebola while working for the aid group Samaritan’s Purse in Liberia last week. Samaritan’s Purse has described them as being in grave but stable condition.
“The two Americans who contracted Ebola in Liberia remain in the country today but medical evacuation efforts are underway and should be completed by early next week,” Samaritan’s Purse said in a statement Friday.
Several aid organizations, including the Peace Corps, are asking volunteers and nonessential personnel to leave the region. The evacuation of these staff members has begun, Samaritan’s Purse said.
Where is this medical plane now?
Where would it land when it returns?
The plane took off from Cartersville Airport in Georgia, about an hour northwest of the CDC’s headquarters in Atlanta. It is unclear where it would land when it returns. The CDC’s quarantine station in Atlanta is housed at Hartsfield-Jackson Atlanta International Airport on the south side of the city.
Where are the patients going?
At least one of the patients will be brought to Emory University, which is near the CDC’s headquarters, hospital officials told CNN’s Dr. Sanjay Gupta. He or she would likely be transported in an Emory ambulance or medical helicopter from the airport.
Emory University Hospital has a specially built isolation unit that is designed to treat patients exposed to infectious diseases like Ebola, the hospital said in a statement Thursday. It is one of only four units in the United States.
“Emory University Hospital physicians, nurses and staff are highly trained in the specific and unique protocols and procedures necessary to treat and care for this type of patient,” the statement said. “These procedures are practiced on a regular basis throughout the year so we are fully prepared for this type of situation.”
When will the patient(s) arrive?
The hospital said staff members do not know specifically when the patient will arrive in Atlanta, just that it will happen “within the next several days.”
What treatment will they receive?
There is no specific treatment for Ebola. Doctors can only administer what they call “supportive therapy,” which means supporting the patient’s own immune system as it tries to battle the infection. This usually involves intravenous fluids to prevent dehydration and shock. This therapy for Ebola patients could also include blood or platelet transfusions and oxygen therapy.
Ebola can last two to three weeks, so patients would remain in isolation until their symptoms subside and tests come back negative for the virus.
Should I be worried?
If the infected aid workers return, it will be the first time someone infected with Ebola is known to have crossed into the United States. That realization has prompted fear among some on social media.
But U.S. health experts don’t seem concerned about it spreading for two reasons:
One, Ebola is aggressively infectious, which means that those infected are highly likely to get sick. But it’s not very contagious, meaning it doesn’t spread easily. It’s transmitted only through bodily fluids while the infected patient is exhibiting symptoms.
And two, experts say our health care system would be able to identify and contain the virus swiftly.
Have other aid workers been affected?
Yes. A well-known doctor fighting Ebola in Sierra Leone died this week after contracting the virus.
“To date, more than 60 health care workers have lost their lives in helping others. Some international staff are infected,” Chan said. “These tragic infections and deaths significantly erode response capacity.”
By Jacque Wilson
CNN’s Ben Brumfield contributed to this story.
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