Since the outbreak of Ebola in West Africa early this year, more than 4,500 people are reported to have died but some patients have survived. So the question remains, why have some patients died and others survived.
Ebola is spread mainly through contact with body fluids of an infected person or a corpse of one that has died of the Ebola virus disease.
A nurse infected with the virus in Spain has recovered, two aid Americans who got infected with the virus while in West Africa, survived the disease when they received an experimental drug and were brought back to the U.S. for treatment and have returned to their families.
But most of the people in Liberia have died on the same disease.
So the questions on the minds of many people are, what is different with all the people that have survived the deadly Ebola virus? What went into caring for them? Why have others still died despite receiving the same experimental drug? And what did doctors learn that could be useful moving forward?
Dr. Joseph McCormick of the University of Texas School of Public Health says it is not yet clear why Ebola runs a different course in different people, but how rapidly symptoms appear depends partly on how much virus a patient was initially exposed to.
Evidence from an American organization, Emory Healthcare indicates that Ebola can be beaten if using the right approach.
Specialists say if a patient is provided with intravenous fluids and nutrients early and you maintain blood pressure, the body of the victim can fight the virus.
If the above is not done, it will lead to vomiting and diarrhea, which will cause dehydration. Then the patient’s blood vessels will start to leak, causing blood pressure to drop to dangerous levels and fluid to build up in the lungs.
The World Health Organization has made clear that there’s far more virus in blood, vomit and feces than in other bodily fluids.
“The key issue is balance between keeping their blood pressure up by giving them fluids, and not pushing them into pulmonary edema where they’re literally going to drown,” McCormick said.
Dr. Bruce Ribner, who runs Emory’s infectious disease unit says that, “most patients, if they have not had any substantial organ damage, will make a full recovery.”
He said that it’s important for doctors and nurses to focus on replacing potassium, calcium and other electrolytes in Ebola patients who are rapidly losing fluids.
“One guidance we are giving back to our colleagues is that they need to pay attention to replacing these electrolytes,” he said. “Even if they’re unable to do the same tests [as Emory did], there are things they can do to try to improve outcomes.”
But survival also can depend on how rapidly someone gets care. It also may be affected by factors beyond anyone’s control: McCormick’s research suggests it partly depends on how the immune system reacts early on — whether too many white blood cells die before they can fight the virus. Other research has linked genetic immune factors to increased survival.
So apart from high-quality treatment, plasma transfusions and quick rehydration, another factor is that experimental drugs have helped some patients survive the Ebola virus. However, medication that hasn’t gone through clinical trials can be risky.
But with a mortality rate of 50% in the current Ebola outbreak, a WHO panel said it is ethical to offer drugs to fight the virus — even if their effectiveness or adverse effects are unknown.
The experimental drugs at the center of this Ebola outbreak are ZMapp, Favipiravir, Brincidofovir and TKM-Ebola.
The director of Emory’s Infectious Disease Unit cautioned against viewing ZMapp as a surefire cure.
“They are the very first individuals to have ever received this agent,” Dr. Bruce Ribner said. “There is no prior experience with it, and frankly, we do not know whether it helped them, whether it made no difference, or even, theoretically, if it delayed their recovery.”
Ebola spreads by contact with bodily fluids, such as through a break in the skin or someone with contaminated hands touching the eyes or nose.