Ebola
Mortality
Data from the World Health Organization (WHO), shows that the chances of dying from Ebola virus infection are about 50-percent, with variations between 25 to 90-percent, depending on the strain and the origin of the outbreak. There are five different strains, with the Zaire type of Ebola being the most aggressive, carrying the highest mortality rate – of over 90-percent. Ebola outbreaks occur in villages in central and Western Africa, where medical care is limited, and most of the regions are unprepared, undersupplied, or under-staffed to handle a massive outbreak of infectious disease. Furthermore, many of these areas are war-zones where Ebola responders are unable to fight the outbreaks or are even killed trying to save people.
There is no cure. Like most other hemorrhagic fevers, there is no cure for the Ebola virus. The best health professionals and patients can hope for is a system of “supportive care,” where infected patients receive extra oxygen, hydration fluids, blood transfusions, and blood pressure monitoring.
There is no cure. Like most other hemorrhagic fevers, there is no cure for the Ebola virus. The best health professionals and patients can hope for is a system of “supportive care,” where infected patients receive extra oxygen, hydration fluids, blood transfusions, and blood pressure monitoring.
Virus Evolution
During the Ebola epidemic that ravaged West Africa in 2014 and 2015, that form of Ebola showed possible signs of evolving. Virologists are still trying to determine the significance of what happened. The epidemic began in a village in Guinea, in December, 2013, when some particles of Ebola apparently went from a bat into a small boy. That strain of the virus, now referred to as Makona Ebola, killed the boy and most of his family, and then began spreading. In the end, around thirty thousand people were infected and more than eleven thousand died before Makona Ebola was finally brought under control and eliminated from the human population. (There were eleven cases in the United States.)
As the epidemic progressed, a team of researchers, led by Pardis Sabeti, a genomic scientist at Harvard and the Broad Institute, studied the genetic code of various samples of Ebola taken from the blood of people who had been infected. They found that the virus began mutating as soon as it got into people. “From the outset, I was intrigued by the large number of mutations we found,” Sabeti told me. Makona Ebola quickly developed into several basic varieties. Then, in late May, 2014, one of the lineages took off like a wildfire and spread rapidly all over Sierra Leone and Liberia. This lineage is named the A82V Makona Variant of Ebola. For simplicity, I’ll call it the Makona mutant. The majority of patients in the epidemic were infected with the Makona mutant, including all eleven individuals in the United States. Meanwhile, the other lineages of Ebola died out. It seemed that the Makona mutant had somehow beaten them in a contest for survival.
Right now, there may be around six hundred people in eastern Congo who have Kivu Ebola particles replicating in their bodies. As Ebola re-creates itself, many of the resulting particles are deformed duds and can’t replicate further. The ones that can copy themselves are infective. The Kivu swarm, with its three new lineages of Ebola, may amount to about one or two quadrillion infective particles of the virus. If these particles were collected in one place, they would fill three teaspoons and would weigh about fifteen grams. That small space contains numberless genetic possibilities. The longer the outbreak is allowed to continue, the greater the chances that Ebola will mutate, get better at spreading in humans, and vastly enlarge its circle of victims.
As the epidemic progressed, a team of researchers, led by Pardis Sabeti, a genomic scientist at Harvard and the Broad Institute, studied the genetic code of various samples of Ebola taken from the blood of people who had been infected. They found that the virus began mutating as soon as it got into people. “From the outset, I was intrigued by the large number of mutations we found,” Sabeti told me. Makona Ebola quickly developed into several basic varieties. Then, in late May, 2014, one of the lineages took off like a wildfire and spread rapidly all over Sierra Leone and Liberia. This lineage is named the A82V Makona Variant of Ebola. For simplicity, I’ll call it the Makona mutant. The majority of patients in the epidemic were infected with the Makona mutant, including all eleven individuals in the United States. Meanwhile, the other lineages of Ebola died out. It seemed that the Makona mutant had somehow beaten them in a contest for survival.
Right now, there may be around six hundred people in eastern Congo who have Kivu Ebola particles replicating in their bodies. As Ebola re-creates itself, many of the resulting particles are deformed duds and can’t replicate further. The ones that can copy themselves are infective. The Kivu swarm, with its three new lineages of Ebola, may amount to about one or two quadrillion infective particles of the virus. If these particles were collected in one place, they would fill three teaspoons and would weigh about fifteen grams. That small space contains numberless genetic possibilities. The longer the outbreak is allowed to continue, the greater the chances that Ebola will mutate, get better at spreading in humans, and vastly enlarge its circle of victims.
Poverty, Climate Change and Future Epidemics
People can catch Ebola by coming into close contact with the blood or bodily fluids of an infected person or animal. Scientists suspect that a fruit bat may have been behind the outbreaks in West Africa in 2014 that killed 11,325 people. The effects of climate change could change where both bats and people live, putting them in closer contact with each other. Poverty — which other studies have shown may also increase in a warming world — can also lead to people turning to more risky sources of food, including wild animals that carry Ebola. And in places where poverty might put people at greater risk, there often aren’t hospitals and clinics with the resources to stop the disease from spreading.
As climate change messes with ecosystems, scientists and doctors have worried that outbreaks of zoonotic diseases (those that can spread from animals to humans) could become harder to predict. Ticks and mosquitos have already been on the move, thanks to warmer temperatures, bringing diseases like Lyme, Dengue, and Zika with them. “Contact opportunity and frequency are crucial drivers in infectious disease spread,” Konstans Wells, an ecologist at Swansea University, wrote to The Verge in an email.
To figure out the outlook for Ebola in 2070, [computer] researchers considered different scenarios for how the world might work together to reduce inequality, slow population growth, and cut greenhouse gas emissions. They saw the likelihood of new outbreaks jump unless people took action to combat each of those factors. [Their mathematical model] predicts that Ebola outbreaks could become as much as 60 percent more likely by 2070 if the world continues on a path toward a warmer climate and a cooling economy.
As climate change messes with ecosystems, scientists and doctors have worried that outbreaks of zoonotic diseases (those that can spread from animals to humans) could become harder to predict. Ticks and mosquitos have already been on the move, thanks to warmer temperatures, bringing diseases like Lyme, Dengue, and Zika with them. “Contact opportunity and frequency are crucial drivers in infectious disease spread,” Konstans Wells, an ecologist at Swansea University, wrote to The Verge in an email.
To figure out the outlook for Ebola in 2070, [computer] researchers considered different scenarios for how the world might work together to reduce inequality, slow population growth, and cut greenhouse gas emissions. They saw the likelihood of new outbreaks jump unless people took action to combat each of those factors. [Their mathematical model] predicts that Ebola outbreaks could become as much as 60 percent more likely by 2070 if the world continues on a path toward a warmer climate and a cooling economy.
Sources:
"14 Important Facts You Should Know About Ebola", SimplyHealth.io, Accessed: November 30, 2019, https://simplyhealth.io/14-important-facts-you-should-know-about-ebola/7/
Justine Calma, "New Computer Model Predicts Where Ebola Might Strike Next", The Verge, October 15, 2019, https://www.theverge.com/2019/10/15/20916188/computer-model-ebola-outbreak-predictionclimate-change-poverty
Richard Preston, "Is Ebola Evolving Into a Deadlier Virus?", The New Yorker, August 7, 2019, https://www.newyorker.com/science/elements/is-ebola-evolving-into-a-more-deadly-virus
Justine Calma, "New Computer Model Predicts Where Ebola Might Strike Next", The Verge, October 15, 2019, https://www.theverge.com/2019/10/15/20916188/computer-model-ebola-outbreak-predictionclimate-change-poverty
Richard Preston, "Is Ebola Evolving Into a Deadlier Virus?", The New Yorker, August 7, 2019, https://www.newyorker.com/science/elements/is-ebola-evolving-into-a-more-deadly-virus