A pale rider

When he opened the fourth seal, I heard the voice of the fourth living creature say, “Come!” And I looked, and behold, a pale horse! And its rider’s name was Death, and Hades followed him. And they were given authority over a fourth of the earth, to kill with sword and with famine and with pestilence and by wild beasts of the earth. (Revelation 6:7-8)

Steve Hays mentions various ways infectious disease could make a comeback in the modern world in his post “The four horsemen of the apocalypse“:

Among other things, the pale horse represents epidemics triggered by infectious disease. You might think this is one of the most dated aspects of the vision. Hasn’t modern medicine done much to eradicate pandemics? True, but that could revert overnight:

i) Overprescription of antibiotics and antivirals has generated superbugs.

ii) Progressive policies funnel immigrants into the country who haven’t been screened for contagious disease. In addition, traditional Muslims have prescientific views of hygiene.

iv) The general public is losing resistance to contagious disease, due both to the diluting effect of uncontrolled immigration–as well as progressive elites at the helm of the antivaxxer movement.

iii) Likewise, welfare is a magnet for urban concentrations of homeless men and women. This leads to the breakdown of public sanitation.

iv) In addition, green policies promote composting rather than standard food disposal. That attracts rats, which multiply exponentially.

A side effect of affluence is to make many people indulge a false sense of security. Affluence creates a buffer. The affluent aren’t used to living on the edge, where there’s no margin for error. They lose their sense of danger. In addition, most folks are crisis-driven. Hazards are an abstraction. They are used to feeling safe, so they lower their guard. But the world is an unforgiving place. Just consider the following scenario:

Dr. Drew Pinsky: Entire Population of California Could Fall Victim To Bubonic Plague Due To Homelessness

The warning is focussed on LA, but all up and down the West coast, urban centers have become a haven for illegal immigrants and the homeless. While many infections diseases are curable, the system is easily overloaded. For instance, the black plague is curable, but because it’s rare, hospitals lack the resources to contain a serious outbreak.

I’d like to add the following:

1. Humans weaponizing pathogens. Biowarfare. Like the Soviet Biopreparat successfully weaponizing the plague, smallpox, and anthrax. Not to mention the Biopreparat successfully hybridized the smallpox with ebola (Ebolapox).

2. Deadly pathogens stored in facilities are accidentally released.

3. Long buried (“prehistoric”) dangerous diseases (e.g. anthrax). This could partly be due to melting permafrost reviving dormant diseases.

4. Antibiotic, antiviral, and other related R&D fails to keep up with the microevolution of pathogens. This is already happening.

5. Weakened human immune systems in subsequent generations (e.g. hygiene hypothesis).

6. It’s become trendy in certain parts of the world to eat foods that might not be safe to eat under certain circumstances (e.g. some raw meats).

7. Sexually transmitted diseases due to increased rates of sexual promiscuity. For example, syphilis was almost eradicated in the US near the turn of the 21st century, but today it’s more prevalent than ever.

A deep sleep

I only watched the first 2 or 3 minutes where Jeff Durbin tells his story. I didn’t watch the rest of the video because the person who made the video said that was all of Durbin’s story and he now he was going to go back and comment on what Durbin said. So I’m just evaluating Durbin’s story, not the commentary following Durbin’s story. From what I watched, I’d say:

1. It seems like Durbin’s main message is that a Christian worldview is largely responsible for modern science including modern medicine. If so, then I agree with this main message. In fact, it’s been documented by scholars like Rodney Stark (e.g. For the Glory of God: How Monotheism Led to Reformations, Science, Witch-Hunts, and the End of Slavery) as well as James Hannam (e.g. The Genesis of Science: How the Christian Middle Ages Launched the Scientific Revolution). So I think this main idea is true.

2. I would also add atheism as a worldview can’t explain as well as Christianity can fundamental principles that are presupposed in science (e.g. the rational intelligibility of the universe). What’s more, atheists like Lawrence Krauss (whom Durbin mentions) subscribe to scientism, which is self-refuting. The idea is that science is the only means to true knowledge. However, it’s easily refuted by the fact that the claim “science is the only means to true knowledge” wasn’t derived using science so we can’t know it’s true if the claim is true!

3. As far as anesthesia, I think Durbin is referring to Gen 2:21 when he’s talking about Genesis and anesthesia: “So the Lord God caused a deep sleep to fall upon the man, and while he slept took one of his ribs and closed up its place with flesh.” Durbin is saying God is the first anesthesiologist because God caused “a deep sleep” to fall on Adam, and presumably a painless sleep, which is what anesthesiology is all about. (By the way, if that’s true, then this verse could also be saying God is the first surgeon, because it sounds like God operated on Adam, removed a rib, and closed it all up!) There’s some truth to this, but the problem is I don’t think there’s a direct line from point A (Gen 2:21) to point B (modern anesthesia). It’s not as simple, clear, or linear as Durbin seems to think it is. Durbin is glossing over a lot of the modern history of anesthesia by trying to make a beeline between the two.

4. Durbin only mentioned one person involved in the discovery and development of modern anesthesia, though he didn’t say who he was referring to. However, there were several people involved. For example, here’s what Morgan and Mikhail’s Clinical Anesthesiology (5th ed.) says about the history of modern anesthesia:

Because the hypodermic needle was not invented until 1855, the first general anesthetics were destined to be inhalation agents. Diethyl ether (known at the time as “sulfuric ether” because it was produced by a simple chemical reaction between ethyl alcohol and sulfuric acid) was originally prepared in 1540 by Valerius Cordus. Ether was used for frivolous purposes (“ether frolics”), but not as an anesthetic agent in humans until 1842, when Crawford W. Long and William E. Clark independently used it on patients for surgery and dental extraction, respectively. However, neither Long nor Clark publicized his discovery. Four years later, in Boston, on October 16, 1846, William T.G. Morton conducted the first publicized demonstration of general anesthesia for surgical operation using ether. The dramatic success of that exhibition led the operating surgeon to exclaim to a skeptical audience: “Gentlemen, this is no humbug!”

Chloroform was independently prepared by Moldenhawer, von Liebig, Guthrie, and Soubeiran around 1831. Although first used by Holmes Coote in 1847, chloroform was introduced into clinical practice by the Scot Sir James Simpson, who administered it to his patients to relieve the pain of labor. Ironically, Simpson had almost abandoned his medical practice after witnessing the terrible despair and agony of patients undergoing operations without anesthesia.

Joseph Priestley produced nitrous oxide in 1772, and Humphry Davy first noted its analgesic properties in 1800. Gardner Colton and Horace Wells are credited with having first used nitrous oxide as an anesthetic for dental extractions in humans in 1844…

The medicinal qualities of coca had been recognized by the Incas for centuries before its actions were first observed by Europeans. Cocaine was isolated from coca leaves in 1855 by Gaedicke and was purified in 1860 by Albert Niemann. Sigmund Freud performed seminal work with cocaine. Nevertheless, the original application of cocaine for anesthesia is credited to Carl Koller, at the time a house officer in ophthalmology, who demonstrated topical anesthesia of the eye in 1884. Later in 1884 William Halsted used cocaine for intradermal infiltration and nerve blocks (including blocks of the facial nerve, brachial plexus, pudendal nerve, and posterior tibial nerve). August Bier is credited with administering the first spinal anesthetic in 1898. He was also the first to describe intravenous regional anesthesia (Bier block) in 1908. Procaine was synthesized in 1904 by Alfred Einhorn and within a year was used clinically as a local anesthetic by Heinrich Braun. Braun was also the first to add epinephrine to prolong the duration of local anesthetics. Ferdinand Cathelin and Jean Sicard introduced caudal epidural anesthesia in 1901. Lumbar epidural anesthesia was described first in 1921 by Fidel Pages and again (independently) in 1931 by Achille Dogliotti. Additional local anesthetics subsequently introduced include dibucaine (1930), tetracaine (1932), lidocaine (1947), chloroprocaine (1955), mepivacaine (1957), prilocaine (1960), bupivacaine (1963), and etidocaine (1972). The most recent additions, ropivacaine (1996) and levobupivacaine (1999), have durations of action similar to bupivacaine but less cardiac toxicity (see Chapter 16). Another, chemically dissimilar local anesthetic, articaine, has been widely applied for dental anesthesia.

Black fire

HolyWrath24 describes what he believed to have been a near death experience (NDE):

Sure. I am on antiphycicotics [antipsychotics] and several years back when I first started taking the medicine I had a day where I drank to many energy drinks. Essentially what happens is that when you sleep you have to maintain a certain body temperature, if you overheat while on these drugs you can die. So I have insomnia as a symptom. I fell asleep but I started to over heat while I was asleep and the excess caffeine in my system was pushing my heart way too hard. I found myself in a large casem [chasm] sort of like the inside of a volcano. There were little wooden shacks all over the walls and it was insainly hot. I found myself inside one of these shacks. There were little black Spirit children that looked like they were on fire with this black fire and they had these evil smiles. They were in these shacks and they controlled these little black wolf creatures. They were chopping people’s bodies up with cleavers. I was in this space but I must have been able to crawl off the chop table and onto the floor but I looked back and my legs had been chopped off up to my knees. So I was crawling away and these wolf’s were barking at me while the kids just smiled and laughed. I saw the door to exit the room it was pink but as I was crawling toward it I started to pray oh Lord I’m so sorry for all that I have done please forgive me don’t leave me here. At that moment the door busted open and a white flash so bright it blinded me came speeding into the room I was picked up and my very essence was carried out into the casem [chasm] and I could feel us flying out so fast I could feel the skin on my face being pressed in by the speed. We flew out of that place with the ominous noise slowly fadeing away. I woke up briefly and called for help, I live with my parents. And then I blacked out again. I woke up briefly again with my mom dragging me to the bathroom. Then I passed out. Then I woke up again in the shower with cold water raining down on me and my mom was slapping me in the face and crying uncontrollably to try to wake me up. Eventually I woke up and was able to move around again. That was the night I gave my life to Christ.

Ars moriendi

In 2008, the national Coping with Cancer project published a study showing that terminally ill cancer patients who were put on a mechanical ventilator, given electrical defibrillation or chest compressions, or admitted, near death, to intensive care had a substantially worse quality of life in their last week than those who received no such interventions. And, six months after their death, their caregivers were three times as likely to suffer major depression. Spending one’s final days in an ICU because of terminal illness is for most people a kind of failure. You lie attached to a ventilator, your every organ shutting down, your mind teetering on delirium and permanently beyond realizing that you will never leave this borrowed, fluorescent place. The end comes with no chance for you to have said good-bye or “It’s okay” or “I’m sorry” or “I love you.”

People with serious illness have priorities besides simply prolonging their lives. Surveys find that their top concerns include avoiding suffering, strengthening relationships with family and friends, being mentally aware, not being a burden on others, and achieving a sense that their life is complete. Our system of technological medical care has utterly failed to meet these needs, and the cost of this failure is measured in far more than dollars. The question therefore is not how we can afford this system’s expense. It is how we can build a health care system that will actually help people achieve what’s most important to them at the end of their lives.

In the past, when dying was typically a more precipitous process, we did not have to think about a question like this. Though some diseases and conditions had a drawn-out natural history—tuberculosis is the classic example—without the intervention of modern medicine, with its scans to diagnose problems early and its treatments to extend life, the interval between recognizing that you had a life-threatening ailment and dying was commonly a matter of days or weeks. Consider how our presidents died before the modern era. George Washington developed a throat infection at home on December 13, 1799, that killed him by the next evening. John Quincy Adams, Millard Fillmore, and Andrew Johnson all succumbed to strokes and died within two days. Rutherford Hayes had a heart attack and died three days later. Others did have a longer course: James Monroe and Andrew Jackson died from progressive and far longer-lasting (and highly dreaded) tubercular consumption. Ulysses Grant’s oral cancer took a year to kill him. But, as end-of-life researcher Joanne Lynn has observed, people generally experienced life-threatening illness the way they experienced bad weather—as something that struck with little warning. And you either got through it or you didn’t.

Dying used to be accompanied by a prescribed set of customs. Guides to ars moriendi, the art of dying, were extraordinarily popular; a medieval version published in Latin in 1415 was reprinted in more than a hundred editions across Europe. People believed death should be accepted stoically, without fear or self-pity or hope for anything more than the forgiveness of God. Reaffirming one’s faith, repenting one’s sins, and letting go of one’s worldly possessions and desires were crucial, and the guides provided families with prayers and questions for the dying in order to put them in the right frame of mind during their final hours. Last words came to hold a particular place of reverence.

These days, swift catastrophic illness is the exception. For most people, death comes only after long medical struggle with an ultimately unstoppable condition—advanced cancer, dementia, Parkinson’s disease, progressive organ failure (most commonly the heart, followed in frequency by lungs, kidneys, liver), or else just the accumulating debilities of very old age. In all such cases, death is certain, but the timing isn’t. So everyone struggles with this uncertainty—with how, and when, to accept that the battle is lost. As for last words, they hardly seem to exist anymore. Technology can sustain our organs until we are well past the point of awareness and coherence. Besides, how do you attend to the thoughts and concerns of the dying when medicine has made it almost impossible to be sure who the dying even are? Is someone with terminal cancer, dementia, or incurable heart failure dying, exactly?

I was once the surgeon for a woman in her sixties who had severe chest and abdominal pain from a bowel obstruction that had ruptured her colon, caused her to have a heart attack, and put her into septic shock and kidney failure. I performed an emergency operation to remove the damaged length of colon and give her a colostomy. A cardiologist stented open her coronary arteries. We put her on dialysis, a ventilator, and intravenous feeding, and she stabilized. After a couple of weeks, though, it was clear that she was not going to get much better. The septic shock had left her with heart and respiratory failure as well as dry gangrene of her foot, which would have to be amputated. She had a large, open abdominal wound with leaking bowel contents, which would require weeks of twice-a-day dressing changes and cleansing in order to heal. She would not be able to eat. She would need a tracheostomy. Her kidneys were gone, and she would have to spend three days a week on a dialysis machine for the rest of her life.

She was unmarried and without children. So I sat with her sisters in the ICU’s family room to talk about whether we should proceed with the amputation and the tracheostomy.

“Is she dying?” one of the sisters asked me.

I didn’t know how to answer the question. I wasn’t even sure what the word “dying” meant anymore. In the past few decades, medical science has rendered obsolete centuries of experience, tradition, and language about our mortality and created a new difficulty for mankind: how to die.

(Atul Gawande, “Letting Go”, Being Mortal: Medicine and What Matters in the End.)

Sleep paralysis

I’ve transcribed some comments on sleep paralysis made by sleep physician Raj Dasgupta (approximately 34:30 to 36:30):

Dasgupta: Sleep paralysis, it’s scary. There’s a disconnect between the mind and the body. Someone asked me, “why does it happen?”. It’s because your mind is awake, but your body is still stuck in REM sleep. What makes REM sleep so unique than any other stage of sleep is you lose muscle tone. Is that a good thing that happens? Of course. It’s a protective mechanism.

Ian: So you don’t act out your dreams?

Dasgupta: You got it. There are disorders out there that I see where patients are re-enacting their dreams. It’s called REM movement disorder. So it’s the opposite. You know, when you ask someone about sleep paralysis, they have these feelings like someone is sitting on their chest, someone is standing in the room, like an ominous figure sometimes. And you know why? What stage of sleep do we see sleep apnea in the most? REM! That’s why you feel that closure of the airway, your breathing becomes shallow.

Ian: So you’re conscious, but your body is still paralyzed?

Dasgupta: You got it. That’s why they feel someone sitting on their chest, and why they think people are in the room, because your mind becomes in this hyper-aroused state. Kind of a protective state. And you get these hallucinations.

1. As a point of clarity, I think the term “sleep paralysis” is a bit misleading, for neither the real concern of the patient nor the primary issue in the disease is the “paralysis” during sleep. Rather, the real concern and the primary issue is what the patient sees or experiences: the presence of an “ominous” entity. Hence traditional terms like “night hag” or “old hag” or “ghost on body” (Chinese) seem more appropriate.

2. Sure, the cause of sleep paralysis could be due to normal sleep physiology in some or many cases. However, I don’t see how normal sleep physiology is necessarily the cause in all cases.

3. If this is always the case, then wouldn’t people with sleep apnea typically experience sleep paralysis? Yet many if not most people with sleep apnea don’t experience sleep paralysis. Not in the sense of an “ominous figure”. Otherwise one is making an equivocation between literal “sleep paralysis” and the night hag.

4. Similarly, there are people in a “hyper-aroused state” who don’t get any “ominous” types of hallucinations. Suppose a drug abuser gets hallucinations. That doesn’t mean the hallucinations will be of a nefarious sort. They could be quite pleasurable.

On the flipside, perhaps there are people who experience the old hag but aren’t necessarily in a “hyper-aroused state”. That might take sleep studies to determine. Granted, there may be slight hiccups in conducting such an experiment. For instance, if the cause is a personal agent, say a demonic entity, then it might be more akin to trying to catch a tiger. The tiger may or may not show up!

5. I may do a separate post on the medical science in the future.

Respecting the human form

32.130.2
(Adoration of the Shepherds, Andrea Mantegna)

The claims of a young Chinese researcher, He Jiankui, to have produced the first people born with edited genomes – twin baby girls – were met with alarm by many scientists. A leading philosopher looks beyond the risks involved in such techniques to the deeper ethical problems of attempting to overcome human nature.

Respecting the human form: the art and ethics of gene editing
By John Haldane

Anyone who has had the good fortune to see the magnificent exhibition of paintings by Mantegna and Bellini at the National Gallery in London (continuing until 29 January) will have been struck by their attention to the human form: at once expert in rendering contour, proportion and volume but also perceptive in capturing or expressing posture, gesture and meaning. Some of those depicted, such as Loredan, Doge of Venice, are great and famous; others, like the shepherds approaching the Virgin and child, are humble and anonymous; and in the figure of Jesus, whether as cradled infant, crucified man or resurrected saviour, the artists endeavour to show us the transcendent in and beyond nature.

However ancient the period, unfamiliar the setting or dramatic the scene, the human form appears as a constant: a common element in art, history, philosophy, politics and religion. Anthropology and the interpretation of ancient texts and artefacts are made possible by and confirm the commonality of humankind. As the Roman dramatist and former slave Terence wrote: “I am human and nothing human is alien to me.” To endorse this maxim is not to say that no human condition is better or worse than any other, for there is both soundness and defect of body, mind and spirit. But both good and bad are identified by reference to the human form, considered not just physiologically, but psychologically, morally and spiritually.

Doge_Leonardo_Loredan
(Portrait of Doge Leonardo Loredan, Giovanni Bellini)

The patrician figure who appears in Bellini’s portrait of the Venetian Doge carries his inherited features as proudly as his official robes, and it did not require the theory of genetics to understand that physical and mental characteristics are inherited. Selective breeding goes back before the Greeks and Romans, but they certainly favoured it in the shaping of human offspring. The modern science of genetics dates from the mid-nineteenth century when an Augustinian friar, Gregor Mendel, when hybridising plants, realised that traits are produced not by the blending of “parental” characteristics but by the combination and interaction of units of inheritance. What those units were and how many of them there are would only be discovered in the following century, with the development of molecular genetics.

As in most other areas of scientific enquiry, our knowledge of genetics is growing rapidly. The largest collaborative undertaking in the history of biology was launched in 1990 and completed a little over a decade later. The identification and mapping of the human genome involved determining the molecular components in human DNA and the segments and sequencing of those that constitute genes. Because genes have structural and functional effects the success of the Human Genome Project prompted questions about the practical application of this knowledge.

The detail and precision of the mapping, together with the influence of causal determinism pervasive within quantitative theories and explanations, encouraged the idea that the genetic make-up of individuals necessarily leads to specific outcomes. But as Mendel suspected when he criticised the earlier theory that the character of the offspring is a blend of the traits found in the parents, the way in which the character of human progeny is determined by that of their ancestors may be complex and indeterminate. In the case of contemporary genetics four factors stand in the way of any simple projections upwards from the genotype to the phenotype (ie from the genes in our DNA responsible for a particular trait to observable physical properties and behaviour). First, there are variations in the genomes of individuals, so one cannot appeal simply to general patterns to be found in the overall human genome. Second, few features are monogenic, rather they depend on interactions between numbers of genes. Third, those interactions, and the expression of individual genes in fixing the structure and function of cells, is subject to external environmental influences. And fourth, individual human bodies themselves contain a vast population of symbiotic micro-organisms whose presence and behaviour affect the expression of genes.

But as well as these physical facts, there is the significant difference made by consciousness, reflection and reasoning. Even if predictions are forthcoming about the upward effects of biology on the human form in its physiological and behavioural aspects there is also efficacy at the level of thought, so that as well as considering what is predicted, or what would happen, there is also the question of what is morally required or what should happen. I am not suggesting that by channelling our thoughts we can somehow impede or redirect biological processes, as some new age practices and meditative techniques imagine. But that as well as what happens, there is the issue of how to respond to it. It is in relation to the latter that the idea of the human form, or the form of the human, offers insight and guidance.

The issue of applied genetics is not just a speculative one – in one form or other it has been with us for decades. Preimplantation screening and prenatal diagnosis are routinely used to detect abnormalities and mutations (as well, of course, as being used to identify the sex of the embryo) – generally with a view to intervention, usually destructive. Such intervention can be positive, for example when it involves gene therapies intended to supply healthy genes, or when it leads to gene-editing to correct, delete or modify gene sequences. But all of these procedures give rise to ethical questions.

In the case of gene-editing, which has come to greater notice recently through reports that a Chinese scientist, He Jiankui, altered the genes of twin female human embryos to ensure they cannot contract HIV, there is the obvious issue of unpredicted and unpredictable consequences. The use of cellular repair mechanisms to modify DNA by genome editing offers the prospect of correcting mutations and of introducing additional functions. However, it also involves risks of producing harmful mutations. Some of these may result from selecting and cutting genomes that contain unintended sequences, and there is the further issue of the resistance of tissues and cell types to infection and transfection. The effects of this resistance and of additional efforts to overcome it are uncertain.

As with cloning, the risks of cellular mutation, physiological and functional malformation and early death provide several good reasons why we should not proceed with these uncertain and potentially hazardous techniques. However – though this research inevitably involves the creation of embryos for experimentation and destruction – these are contingent and consequential factors which may be overcome through further scientific research. We have to look beyond these risks, and consider deeper ethical and philosophical considerations.

First, it is necessary to distinguish between actions intended to remedy a defect and thereby restore a normal feature, and those aimed at changing the character of a thing, to give it enhanced or additional powers. The former concern repair the latter transformation. Aside from unanticipated immediate effects there is the issue of further collateral consequences. By way of analogy, making people more ambitious may counter lack of attainment, but it may also remove associated circumstantial benefits, such as contentment.

The study of the physical aspects of the human form is the business of the sciences, but the understanding of human life and the place of norms, ideals, principles and values is the business of imaginative, ethical, philosophical and religious reflection. Current discussions of how genetic and reproductive technologies should be combined tend to be conducted almost exclusively in terms of harms and benefits. There are two problems with this: first, the calculations are crudely utilitarian; but second, they omit non-consequential factors. For most people, the challenges of reproduction are felt to be worthwhile and are accepted as the corollary of the creation of another human being. The sense of otherness which is felt at the sight of a newborn child registers a combination of continuity and difference that contributes in part to the value of conceiving and having children. By contrast, the deployment of genetic science in the service of enhanced reproduction suggests a wish to overcome human nature as it is in favour of some unspecified “improved condition”. It may be said that the application of genetics offers the prospect of creating children whose initial condition and subsequent development are likely to be better than those of natural offspring. But this reply embodies a disregard of the human form which is the condition of our existence, and the recognition of which binds us to peoples past or far away.

presentation-of-christ
(Presentation at the Temple, Giovanni Bellini)

A good human life is not one that tries to overcome the human form, but is one that is developed within the context of it. That is why we resonate to the art of Mantegna and Bellini and take hope in the idea that God took on our human form.

John Haldane is a professor of philosophy at Baylor University, Texas, and at the University of St Andrews. He is also a member of the Vatican’s Pontifical Academy for Life.

Why did God create the Ebola virus?

ebola

Infectious disease physician Francisco Delgado offers his response. I’ve copied and pasted it below. See the last paragraph if you don’t wish to read the entire piece.


God’s goodness and the Ebola virus

The Ebola virus is a member of the Filoviridae family. These viruses carry their genetic information in a single strand of negative-sense RNA. They also carry an RNA-dependent RNA polymerase, an enzyme responsible for synthesizing positive-sense and negative-sense viral RNA. The cell machinery then synthesizes the new viral proteins from the positive-sense RNA, leading to the assembly of new viral particles.

Ebola was first identified in 1976, during an outbreak in Zaire (now the Democratic Republic of the Congo). Despite this relatively recent discovery, Ebola does not seem to be a new virus. Researchers have identified filoviral gene sequences in the genomes of some vertebrates and based on phylogenetic analysis of these sequences, they estimate that vertebrates have been exposed to filoviruses since as far back as 40 million years ago. The presence of filoviral sequences in vertebrate DNA also implies that coinfection of filoviruses with retroviruses allows viral RNAs to integrate into the DNA of their hosts. It is important to point out that filoviruses and Bornaviruses were the only families of RNA viruses found integrated into the DNA of vertebrates.1

The reason for this integration is unclear. Research in the area of endogenous retroviruses indicates that the presence of these retroviruses in mammalian cells plays an essential role in placental development.2 It is then possible that the presence of filoviral sequences in vertebrates provides the natural hosts with important elements that could be crucial for their survival.

It is thought that fruit bats are the natural hosts of the Ebola virus. Humans become infected through contact with an infected animal, which could be a bat or an infected primate. Ebola then spreads from human to human through contact with blood or body fluids. Whereas mortality in humans is very high, bats and some other animals seem to develop an asymptomatic infection.

Recent studies on bats have revealed some interesting discoveries. Bats display unique biological features such as long life spans and a low rate of tumor development.3 Recent research has also shown that bats’ immune systems are in a more activated state than other mammals’.4 It is unknown whether exposure to the Ebola virus acts as a primer for the bat immune system to fight other pathogens, as well as tumor cells, or whether these viruses possess direct oncolytic behavior.

Bats are the only flying mammal and they are the second most species-rich mammalian order. They play a very important role in ecosystems around the world, mainly through the consumption of insects. In a sense, bats act as agents of pest control. Filoviruses may then contribute to maintain the health of these animals, providing us with a more hospitable environment to live in (no mosquitoes!) and controlling agricultural pests that could devastate our food supply.

So, Ebola infection in humans can be understood as a break in the carefully balanced ecosystem involving microorganisms and natural hosts. The accidental encounters between Ebola and humans may result in tragic episodes of human death. However, we need to remember that viruses are part of Earth’s ecosystems and that they play a role in keeping our planet in an optimal state to allow for human life to be possible. Filoviruses may reflect another characteristic of careful design by God for the benefit of advanced life on Earth.

References

1 Vladimir A. Belyi, Arnold J. Levine, and Anna Marie Skalka, “Unexpected Inheritance: Multiple Integrations of Ancient Bornavirus and Ebolavirus/Marburgvirus Sequences in Vertebrate Genomes,” PLoS Pathogens 6 (July 2010): DOI:10.1371/journal.ppat.1001030.
2 Christian Lavialle et al., “Paleovirology of ‘Syncytins,’ Retroviral Env Genes Exapted for a Role in Placentation,” Philosophical Transactions of the Royal Society B 368 (September 19, 2013): DOI:10.1098/rstb.2012.0507
3 James W. Wynne and Lin-Fa Wang, “Bats and Viruses: Friend or Foe?,” PLoS Pathogens 9 (October 2013): DOI: 10.1371/journal.ppat.1003651.
4 Guojie Zhang et al., “Comparative Analysis of Bat Genomes Provides Insight into the Evolution of Flight and Immunity,” Science 339 (January 25, 2013): 456–60.