What happens when you survive Ebola?By Jacque Wilson, CNNUpdated 11:20 AM ET, Mon August 25, 2014Photos: The Ebola epidemic 47 photosThe Ebola epidemic – Red Cross workers, wearing protective suits, carry the body of a person who died from Ebola during a burial in Monrovia, Liberia, on Monday, January 5. Since the epidemic started a little more than a year ago in a remote village in Guinea, the world has seen more than 8,400 deaths, according to the latest numbers from the World Health Organization. And that number is believed to be low, since there was widespread under-reporting of cases, according to WHO.Hide Caption 1 of 47Photos: The Ebola epidemic 47 photosPauline Cafferkey, a Scottish woman diagnosed with Ebola, is put on a plane in Glasgow, Scotland, on Tuesday, December 30. Cafferkey, a 39-year-old nurse who volunteered in Sierra Leone, was being transported to London for treatment.Hide Caption 2 of 47Photos: The Ebola epidemic 47 photosLiberian President Ellen Johnson Sirleaf has her temperature taken before the opening of a new Ebola clinic Tuesday, November 25, in Monrovia.Hide Caption 3 of 47Photos: The Ebola epidemic 47 photosA child who survived the Ebola virus is fed by another survivor at a treatment center on the outskirts of Freetown, Sierra Leone, on Tuesday, November 11.Hide Caption 4 of 47Photos: The Ebola epidemic 47 photosHealth workers in Monrovia cover the body of a man suspected of dying from the Ebola virus on Friday, October 31.Hide Caption 5 of 47Photos: The Ebola epidemic 47 photosKaci Hickox leaves her home in Fort Kent, Maine, to take a bike ride with her boyfriend on Thursday, October 30. Hickox, a nurse, recently returned to the United States from West Africa, where she treated Ebola victims. State authorities wanted her to avoid public places for 21 days -- the virus' incubation period. But Hickox, who twice tested negative for Ebola, said she would defy efforts to keep her quarantined at home.Hide Caption 6 of 47Photos: The Ebola epidemic 47 photosCrew members at an airport in Accra, Ghana, unload supplies sent from China on Wednesday, October 29.Hide Caption 7 of 47Photos: The Ebola epidemic 47 photosHealth officials in Nairobi, Kenya, prepare to screen passengers arriving at the Jomo Kenyatta International Airport on Tuesday, October 28.Hide Caption 8 of 47Photos: The Ebola epidemic 47 photosU.S. President Barack Obama hugs Ebola survivor Nina Pham in the Oval Office of the White House on Friday, October 24. Pham, one of two Dallas nurses diagnosed with the virus, was declared Ebola-free after being treated at a hospital in Bethesda, Maryland. The other nurse, Amber Vinson (not pictured), was treated in Atlanta and also declared Ebola-free.Hide Caption 9 of 47Photos: The Ebola epidemic 47 photosHealth workers in Port Loko, Sierra Leone, transport the body of a person who is suspected to have died of Ebola on Tuesday, October 21.Hide Caption 10 of 47Photos: The Ebola epidemic 47 photosHealth workers bury a body on the outskirts of Monrovia on Monday, October 20.Hide Caption 11 of 47Photos: The Ebola epidemic 47 photosGarteh Korkoryah, center, is comforted during a memorial service for her son, Thomas Eric Duncan, on Saturday, October 18, in Salisbury, North Carolina. Duncan, a 42-year-old Liberian citizen, died October 8 in a Dallas hospital. He was in the country to visit his son and his son's mother, and he was the first person in the United States to be diagnosed with Ebola.Hide Caption 12 of 47Photos: The Ebola epidemic 47 photosBoys run from blowing dust as a U.S. military aircraft leaves the construction site of an Ebola treatment center in Tubmanburg, Liberia, on Wednesday, October 15.Hide Caption 13 of 47Photos: The Ebola epidemic 47 photosAid workers from the Liberian Medical Renaissance League stage an Ebola awareness event October 15 in Monrovia. The group performs street dramas throughout Monrovia to educate the public on Ebola symptoms and how to handle people who are infected with the virus.Hide Caption 14 of 47Photos: The Ebola epidemic 47 photosEbola survivors prepare to leave a Doctors Without Borders treatment center after recovering from the virus in Paynesville, Liberia, on October 12.Hide Caption 15 of 47Photos: The Ebola epidemic 47 photosA woman crawls toward the body of her sister as a burial team takes her away for cremation Friday, October 10, in Monrovia. The sister had died from Ebola earlier in the morning while trying to walk to a treatment center, according to her relatives.Hide Caption 16 of 47Photos: The Ebola epidemic 47 photosA person peeks out from the Dallas apartment where Thomas Eric Duncan, the first person diagnosed with the Ebola virus in the United States, was staying on Friday, October 3.Hide Caption 17 of 47Photos: The Ebola epidemic 47 photosA girl cries as community activists approach her outside her Monrovia home on Thursday, October 2, a day after her mother was taken to an Ebola ward.Hide Caption 18 of 47Photos: The Ebola epidemic 47 photosA health official uses a thermometer Monday, September 29, to screen a Ukrainian crew member on the deck of a cargo ship at the Apapa port in Lagos, Nigeria.Hide Caption 19 of 47Photos: The Ebola epidemic 47 photosWorkers move a building into place as part of a new Ebola treatment center in Monrovia on September 28.Hide Caption 20 of 47Photos: The Ebola epidemic 47 photosMedical staff members at the Doctors Without Borders facility in Monrovia burn clothes belonging to Ebola patients on Saturday, September 27. Hide Caption 21 of 47Photos: The Ebola epidemic 47 photosMedics load an Ebola patient onto a plane at Sierra Leone's Freetown-Lungi International Airport on Monday, September 22.Hide Caption 22 of 47Photos: The Ebola epidemic 47 photosA few people are seen in Freetown during a three-day nationwide lockdown on Sunday, September 21. In an attempt to curb the spread of the Ebola virus, people in Sierra Leone were told to stay in their homes.Hide Caption 23 of 47Photos: The Ebola epidemic 47 photosSupplies wait to be loaded onto an aircraft at New York's John F. Kennedy International Airport on Saturday, September 20. It was the largest single shipment of aid to the Ebola zone to date, and it was coordinated by the Clinton Global Initiative and other U.S. aid organizations.Hide Caption 24 of 47Photos: The Ebola epidemic 47 photosA child stops on a Monrovia street Friday, September 12, to look at a man who is suspected of suffering from Ebola.Hide Caption 25 of 47Photos: The Ebola epidemic 47 photosHealth workers in Monrovia place a corpse into a body bag on Thursday, September 4.Hide Caption 26 of 47Photos: The Ebola epidemic 47 photosAfter an Ebola case was confirmed in Senegal, people load cars with household items as they prepare to cross into Guinea from the border town of Diaobe, Senegal, on Wednesday, September 3.Hide Caption 27 of 47Photos: The Ebola epidemic 47 photosCrowds cheer and celebrate in the streets Saturday, August 30, after Liberian authorities reopened the West Point slum in Monrovia. The military had been enforcing a quarantine on West Point, fearing a spread of the Ebola virus.Hide Caption 28 of 47Photos: The Ebola epidemic 47 photosA health worker wearing a protective suit conducts an Ebola prevention drill at the port in Monrovia on Friday, August 29. Hide Caption 29 of 47Photos: The Ebola epidemic 47 photosVolunteers working with the bodies of Ebola victims in Kenema, Sierra Leone, sterilize their uniforms on Sunday, August 24. Hide Caption 30 of 47Photos: The Ebola epidemic 47 photosA burial team from the Liberian Ministry of Health unloads bodies of Ebola victims onto a funeral pyre at a crematorium in Marshall, Liberia, on Friday, August 22.Hide Caption 31 of 47Photos: The Ebola epidemic 47 photosDr. Kent Brantly leaves Emory University Hospital on Thursday, August 21, after being declared no longer infectious from the Ebola virus. Brantly was one of two American missionaries brought to Emory for treatment of the deadly virus.Hide Caption 32 of 47Photos: The Ebola epidemic 47 photosAn Ebola Task Force soldier beats a local resident while enforcing a quarantine on the West Point slum on August 20.Hide Caption 33 of 47Photos: The Ebola epidemic 47 photosLocal residents gather around a very sick Saah Exco, 10, in a back alley of the West Point slum on Tuesday, August 19. The boy was one of the patients that was pulled out of a holding center for suspected Ebola patients after the facility was overrun and closed by a mob on August 16. A local clinic then refused to treat Saah, according to residents, because of the danger of infection. Although he was never tested for Ebola, Saah's mother and brother died in the holding center.Hide Caption 34 of 47Photos: The Ebola epidemic 47 photosA burial team wearing protective clothing retrieves the body of a 60-year-old Ebola victim from his home near Monrovia on Sunday, August 17. Hide Caption 35 of 47Photos: The Ebola epidemic 47 photosWorkers prepare the new Ebola treatment center on August 17.Hide Caption 36 of 47Photos: The Ebola epidemic 47 photosLiberian police depart after firing shots in the air while trying to protect an Ebola burial team in the West Point slum of Monrovia on August 16. A crowd of several hundred local residents reportedly drove away the burial team and their police escort. The mob then forced open an Ebola isolation ward and took patients out, saying the Ebola epidemic is a hoax.Hide Caption 37 of 47Photos: The Ebola epidemic 47 photosA crowd enters the grounds of an Ebola isolation center in the West Point slum on August 16. The mob was reportedly shouting, "No Ebola in West Point."Hide Caption 38 of 47Photos: The Ebola epidemic 47 photosA health worker disinfects a corpse after a man died in a classroom being used as an Ebola isolation ward Friday, August 15, in Monrovia.Hide Caption 39 of 47Photos: The Ebola epidemic 47 photosHealth workers in Kenema screen people for the Ebola virus on Saturday, August 9, before they enter the Kenema Government Hospital.Hide Caption 40 of 47Photos: The Ebola epidemic 47 photosAid worker Nancy Writebol, wearing a protective suit, gets wheeled on a gurney into Emory University Hospital in Atlanta on August 5. A medical plane flew Writebol from Liberia to the United States after she and her colleague Dr. Kent Brantly were infected with the Ebola virus in the West African country. Hide Caption 41 of 47Photos: The Ebola epidemic 47 photosMembers of Doctors Without Borders adjust tents in the isolation area in Kailahun on July 20.Hide Caption 42 of 47Photos: The Ebola epidemic 47 photosBoots dry in the Ebola treatment center in Kailahun on July 20.Hide Caption 43 of 47Photos: The Ebola epidemic 47 photosDr. Jose Rovira of the World Health Organization takes a swab from a suspected Ebola victim in Pendembu, Sierra Leone, on Friday, July 18.Hide Caption 44 of 47Photos: The Ebola epidemic 47 photosRed Cross volunteers disinfect each other with chlorine after removing the body of an Ebola victim from a house in Pendembu on July 18.Hide Caption 45 of 47Photos: The Ebola epidemic 47 photosA scientist separates blood cells from plasma cells to isolate any Ebola RNA and test for the virus Thursday, April 3, at the European Mobile Laboratory in Gueckedou, Guinea.Hide Caption 46 of 47Photos: The Ebola epidemic 47 photosHealth specialists work Monday, March 31, at an isolation ward for patients at the facility in southern Guinea.Hide Caption 47 of 47Story highlightsAmerican patients infected with Ebola are being released from the hospital Dr. Kent Brantly and Nancy Writebol were given ZMapp, an experimental drugTo leave isolation, two blood tests on the Ebola patients must come back negative for the virusTwo American missionaries infected with the deadly Ebola virus were given an experimental drug.Shortly after, Dr. Kent Brantly and Nancy Writebol were flown separately from Liberia to Atlanta's Emory University Hospital -- the first human patients with Ebola to ever come to the United States. Writebol was released from the hospital Tuesday. On Thursday morning, Brantly walked out of that same hospital with no signs of the virus in his system, doctors say.Their recoveries seem to offer hope for those fighting the largest Ebola outbreak in known history. More than 2,400 people have been infected by the virus, according to the World Health Organization, and it's killed more than half. But ZMapp is not an approved treatment for Ebola; in fact, no approved, proven treatment exists. So governments, aid organizations and scientists around the globe are racing to find a way to stop the virus.Just WatchedBrantly: 'I am thrilled to be alive'replayMore Videos ...Brantly: 'I am thrilled to be alive' 02:06PLAY VIDEOJust WatchedPatients arriving at largest Ebola clinicreplayMore Videos ...Patients arriving at largest Ebola clinic 01:11PLAY VIDEOJust WatchedSecret serum likely saved Ebola patient replayMore Videos ...Secret serum likely saved Ebola patient 01:53PLAY VIDEOJust WatchedEbola facility attacked; patients fleereplayMore Videos ...Ebola facility attacked; patients flee 01:33PLAY VIDEOHere are answers to questions about Ebola patients and treatments for the disease. 1. Are Brantly and Writebol cured?Mostly. For Ebola patients to leave isolation, two blood tests had to come back negative for the Ebola virus. So their bodily fluids, like blood, sweat and feces, are no longer infectious."Nancy is free of the virus, but the lingering effects of the battle have left her in a significantly weakened condition," Writebol's husband, David Writebol, said in a statement. Some doctors believe the virus can remain in vaginal fluid and semen for up to several months, according to WHO. Dr. Bruce Ribner, an infectious disease specialist at Emory, said there is no evidence Ebola has ever been transmitted this way, but the risk was discussed with both patients.2. Are they now immune to Ebola?Doctors believe surviving Ebola leaves you immune to future infection. Scientists have found that people who survive Ebola have antibodies in their blood that would provide protection against that strain of the virus in the future, and possibly against other strains as well. But, as you can imagine, they haven't tested this theory by infecting survivors with the virus again. There are four Ebola strains known to infect humans; the Zaire ebolavirus causing the current outbreak is the most common. 3. Who else has been given ZMapp?The Ebola drug was flown to Spain to give to a priest named Miguel Pajares, who had contracted the virus in Liberia. Pajares died on August 12. It's unclear if he was given the drug before he died.ZMapp appears to be helping three Liberian health care workers who were given the experimental drug. They have shown "very positive signs of recovery," the Liberian Ministry of Health said earlier this week. Medical professionals treating the workers have called their progress "remarkable."4. Who makes the drug?The drug was developed by the biotech firm Mapp Biopharmaceutical Inc., which is based in San Diego. The company was founded in 2003 "to develop novel pharmaceuticals for the prevention and treatment of infectious diseases, focusing on unmet needs in global health and biodefense," according to its website. Mapp Biopharmaceutical has been working with the National Institutes of Health and the Defense Threat Reduction Agency, an arm of the military responsible for countering weapons of mass destruction, to develop an Ebola treatment for several years.5. How does ZMapp work?Antibodies are proteins used by the immune system to mark and destroy foreign, or harmful, cells. A monoclonal antibody is similar, except it's engineered in a lab so it will attach to specific parts of a dangerous cell, according to the Mayo Clinic, mimicking your immune system's natural response. Monoclonal antibodies are used to treat many different types of conditions.Sources told CNN the medicine given to Brantly and Writebol abroad was a three-mouse monoclonal antibody, meaning that mice were exposed to fragments of the Ebola virus, and then the antibodies generated within the mice's blood were harvested to create the medicine. However, the drug can also be produced with proteins made from tobacco plants. ZMapp manufacturer Kentucky BioProcessing in Owensboro provided limited quantities of this kind of the drug to Emory, according to company spokesman David Howard. 6. Did doctors know it would work in humans?No. The drug had shown promise in primates, but even in those experiments, just eight monkeys received the treatment. In any case, the human immune system can react differently than primates', which is why drugs are required to undergo human clinical trials before being approved by government agencies for widespread use. These cases will be studied further to determine how the drug worked with their immune systems. 7. Are there other Ebola treatments out there?Several experimental drugs are in development, but none has been effective in humans.The market for these drugs is small -- Ebola is a rare disease, almost completely confined to poor countries -- so funding for drug development has come largely from government agencies. In March, the NIH awarded a five-year, $28 million grant to establish a collaboration between researchers from 15 institutions who were working to fight Ebola. On Wednesday, Wellcome Trust and the United Kingdom's Department for International Development announced money for Ebola research will be made available from a $10.8 million initiative.8. Will ZMapp or these other drugs be given to more Ebola patients?An ethics panel convened by the World Health Organization concluded it is ethical to give experimental drugs during an outbreak as large as this one, but that doesn't mean it will happen. Rolling out an untested drug during a massive outbreak would be very difficult, Doctors Without Borders says. Experimental drugs typically are not mass-produced, and tracking the success of such a drug, if used, would require extra medical staff where resources are already scarce.In an opinion article published in the journal Nature this week, epidemiologist Oliver Brady says up to 30,000 people in West Africa would have so far required treatment in this outbreak if it was available.9. What about an Ebola vaccine?For the record, "vaccine" and "treatment" are not interchangeable terms. A vaccine is given to prevent infection, whereas treatment generally refers to a drug given to a patient who has developed symptoms.There are several Ebola vaccines in development.The Canadian government has donated between 800 and 1,000 doses of an experimental Ebola vaccine to WHO. The drug, called VSV-EBOV, is Canadian-made and owned, having been developed by the National Microbiology Laboratory.It's never been tested on humans "but has shown promise in animal research," the agency says. We don't know if the vaccine has been given to anyone on the ground.The NIH says a safety trial of an Ebola vaccine will start as early as September.Ebola outbreakHow the world reacted as Ebola spreadThe largest Ebola epidemic in history began with the simple act of caring for a child. Soon, it spread from the remote village in Guinea.Countries with travel restrictionsThe worst-ever outbreak of Ebola virus is stretching the medical capacities of Guinea, Liberia and Sierra Leone.Who is patient zero?Before the deaths soared into the thousands, before the outbreak triggered global fears, Ebola struck a toddler named Emile Ouamouno. The messy truth about EbolaWhat happens when you get Ebola? CNN's Miguel Marquez explains.Millions of vaccines planned by 2015 Health experts are fast-tracking tests for various vaccines, and hope to have millions of experimental doses by next year.How the Ebola virus spreadsEbola is a scary infectious disease but the first thing you should know is that it's not very contagious. Here is how it spreads.What you need to knowThese questions and answers will give you the latest information on the deadly virus and what's being done to stop its spread.3 with Ebola will fly each monthUp to three Ebola-infected travelers might board an international flight each month in West Africa, according to a new study, and potentially spread the deadly virus.Why some survive, some don'tThere's no cure for Ebola. So why have some patients walked away healthy while others in the West died? Inside the world's worst outbreakA doctor at a government-run Ebola treatment center in Monrovia is too busy to mince words.Stigmatized, abandoned orphansTwo children orphaned by Ebola play in the empty corner of a Liberian orphanage. Their parents died last month, and none of the extended family is willing to claim them. Five ways the CDC got it wrongPublic health experts are asking whether the CDC is partly to blame for problems with Ebola in the U.S. Here are 5 things they say the CDC is getting wrong.Can pets get or spread Ebola? The lack of solid protocol on what to do with Ebola victims' pets and what little is known about the risk has caused one dog to be euthanized and another quarantined. A look at Ebola protective gearRosie Tomkins takes a look at the protective suits that are worn by some Ebola medical workers in Africa.How hospitals handle Ebola patientsWhat's the protocol for health care workers if they suspect a patient has the virusEbola outbreak in West AfricaClick through our gallery as we track the Ebola outbreak in West Africa. Complete coverage on EbolaA look at CNN's complete coverage on the Ebola crisis. More from health5 things to know about measlesFather asks California school district to ban children who haven't been immunizedFit Nation 2015 team kick off in AtlantaPowered by Livefyre
How the world reacted as Ebola spreadThe largest Ebola epidemic in history began with the simple act of caring for a child. Soon, it spread from the remote village in Guinea.
Countries with travel restrictionsThe worst-ever outbreak of Ebola virus is stretching the medical capacities of Guinea, Liberia and Sierra Leone.
Who is patient zero?Before the deaths soared into the thousands, before the outbreak triggered global fears, Ebola struck a toddler named Emile Ouamouno.
Millions of vaccines planned by 2015 Health experts are fast-tracking tests for various vaccines, and hope to have millions of experimental doses by next year.
How the Ebola virus spreadsEbola is a scary infectious disease but the first thing you should know is that it's not very contagious. Here is how it spreads.
What you need to knowThese questions and answers will give you the latest information on the deadly virus and what's being done to stop its spread.
3 with Ebola will fly each monthUp to three Ebola-infected travelers might board an international flight each month in West Africa, according to a new study, and potentially spread the deadly virus.
Why some survive, some don'tThere's no cure for Ebola. So why have some patients walked away healthy while others in the West died?
Inside the world's worst outbreakA doctor at a government-run Ebola treatment center in Monrovia is too busy to mince words.
Stigmatized, abandoned orphansTwo children orphaned by Ebola play in the empty corner of a Liberian orphanage. Their parents died last month, and none of the extended family is willing to claim them.
Five ways the CDC got it wrongPublic health experts are asking whether the CDC is partly to blame for problems with Ebola in the U.S. Here are 5 things they say the CDC is getting wrong.
Can pets get or spread Ebola? The lack of solid protocol on what to do with Ebola victims' pets and what little is known about the risk has caused one dog to be euthanized and another quarantined.
A look at Ebola protective gearRosie Tomkins takes a look at the protective suits that are worn by some Ebola medical workers in Africa.
How hospitals handle Ebola patientsWhat's the protocol for health care workers if they suspect a patient has the virus
Ebola outbreak in West AfricaClick through our gallery as we track the Ebola outbreak in West Africa.