What you need to know about Ebola
First, let me start out by stating that I am far from an infectious disease expert, and I did not even sleep at a Holiday Inn last night. I did, however, major in Bio-Chemistry Cell and Molecular Biology. I lecture frequently on travel and personal security of which disease risk is a significant factor. Instead of watching football, I read things like “A Stain on Our Humanity” which details the infectious disease experiments conducted by the Japanese in World War II, and periodically burn a few hours on the National Institute of Health reports on containment effectiveness of various global disease outbreaks.
So, when I am not reading about foreign affairs or personal security, shooting at competitions, walking my dog or spending time with my family, this stuff is one of my interests. What I see reported in the news ranges from hysteria to pure fabrication and gross exaggeration. From an amateur’s perspective with a little bit of insight, here is what you should probably know about Ebola provided in hopes of debunking some myths and keeping some reasonableness to the fact that we are in reality facing an unprecedented outbreak.
How long have we known about Ebola?
Ebola was first discovered in Zaire, Africa in 1976. Then 318 people were infected with what has become the predominant strain of the virus referred to as the Zaire Strain. It had a fatality rate of 88% in that outbreak. The subtypes of Ebola are typically referred to by the location they were first discovered. Again in 1976 in Sudan a different strain referred to as the Sudan strain infected 284 people with a fatality rate of 53%. The same strain struck again in the same area three years later in 1979 infecting 34 people with a fatality rate of 65%. We did not identify a new outbreak for nearly a decade.
In 1989 and 1990, what is known as the Reston strain infected laboratory workers, however, they did not develop symptoms. I am choosing to ignore the Reston strain, as it is a laboratory created virus with no fatality associated with it, and does not at this point exist outside of laboratory environments. While useful for research, it is not a good predictor of behavior of the disease in the wild.
From 1990 – 1999 there were 6 more outbreaks of the Zaire strain in Gabon, Ivory Coast, Zaire (DRC), South Africa and Russia (which was a laboratory contamination). The total number of infected people over 10 years was 467, and fatality rates ranged from 60 – 81%. Until recently, the largest outbreak in history was in 2000 when the Sudan Strain infected 425 people in Uganda with a fatality rate of 53%. From 2000 – 2014, we have experienced roughly an annual out break of one of the two primary strains of the virus (Zaire or Sudan). Over 14 years the total number of infected people was 1242. Historically, The Zaire strain is the most severe with an average fatality rate of about 78%. This is followed by the Sudan Strain with a fatality rate of approximately 54%. A newer strain referred to as the Bundibugyo strain infected 149 people in 2007 in Uganda with a fatality rate of 25%.
Since March of 2014, there have been more than 6000 confirmed cases of the Zaire strain in multiple countries and we are currently experiencing about a 51% fatality rate. We can predict based on confirmation rates, and exposure that this number will grow to more than 14,000 cases by the end of October. The Center for Disease controls “worst case” projection is 1.4 million by January 2015.
That is only in its first year. If this disease were to continue at the CDC’s worst-case rate, by the end of year two it will infect 367,001,600,000 people, or about half of the world’s population… Those are the hysteria numbers and roughly where they come from. That is not going to happen, but this outbreak is unprecedented in scope and is far from under control at this point. It is a legitimate global concern, but with a bit of education, common sense and prevention, we can and will contain the disease and hopefully in the near future create effective supportive therapy drugs like ZMapp and potentially even vaccines like TKM-Ebola, which are both being pursued.
Where did Ebola come from?
Ebola may have originated in plants, and we think fruit bats may be the natural host of the disease (the one it doesn’t kill) or where it coexists relatively innocuously, but the fact is we don’t know. There is evidence for and against both theories. We know it is highly pathogenic in vertebrates and tends to be associated with high mortality rates when it infects them.
While the exact mechanism of transmission from Animal to human is unknown, the most likely cause is exposure to infected animal body fluids, or ingestion of uncooked infected tissue. This typically occurs when locals hunt and kill, or find, a dead infected animal (and starving people in Africa do subsist on tissue from bats in remote regions.) In the case of this outbreak, there has not been an animal outbreak confirmed, and many are considering that exposure to the bodily fluids of infected bats as the most likely source. Regardless of how it transferred to humans, it is here.
How does human-to-human transmission occur?
Ebola human-to-human transmission occurs ONLY by exposure to bodily fluids. By bodily fluids, we mean blood, saliva, mucus, semen, feces and even sweat. The disease is not translated through the skin of an uninfected person. To complete the transmission, there must be a break in the skin allowing the virus into the interior bodily fluids and tissue of the uninfected person. Unfortunately, we all have minor breaks in our skin that are more than sufficient to allow transmission if exposed to the fluid of an infected person.
Significantly, the disease is not contagious until the infected person is symptomatic. This is not the case with all diseases, but with Ebola, there is a fairly narrow window between the onset of symptoms and relative incapacitation. It is unlikely that a person who was exhibiting symptoms would feel well enough to travel, go to work or do much outside of their personal domicile. That is not to say that an infected person, could not become infectious over the course of a long plane ride, or tough it out through the airport security line at the early stages. In order to be exposed to the virus, a person must come into contact with the bodily fluids of a person who is symptomatic, and fortunately symptomatic people are unlikely to have the energy to be out and about in public.
What are the symptoms of Ebola?
The development of symptoms range between 2 and 21 days after infection, but on average they manifest between days 8 and 10. Typically the first symptoms are the sudden onset of a severe fever (generally in excess of 101.5 degrees). That fever is accompanied by fatigue, headache, muscle ache and a sore throat. Vomiting, diarrhea, and rash follow shortly thereafter and things deteriorate from there. At this point in the disease, the kidney and liver functions are being greatly impaired due to tissue damage which causes other systemic issues contributing to the high fatality rates. In the last phases of the disease there can be evidence of internal and external bleeding as organs, and tissue around the eyes and gums become damaged to the point they are incapable of containing fluids.
Can I get Ebola from a counter top?
The short answer is yes – maybe. A person infected with Ebola who is exhibiting symptoms would be very likely to leave bodily fluids, (sweat, urine, feces, etc…) in a bathroom. Those fluids could conceivably contain live virus that could infect a healthy person, if they come into contact with it. The virus can survive for about a week in a clean and controlled environment, but a bathroom is very far from a controlled environment. The virus is very unstable outside the body, and is susceptible to U.V. light, oxygen, heat, disinfectants, time and a variety of other things cause it to degrade fairly quickly. It is possible, to be infected by materials used by infected people, but at some point we will make estimates of infection rates from non personal contact, I suspect it will be low on the list on a percentage basis.
Why is this particular outbreak so out of control?
As I was revamping a travel security presentation for the counter-terrorism symposium in New York in February and March of this year, I updated one of my slides to reference the 300 cases of Ebola reported in Guinea. By April 10th & 11th, when I gave the presentation, the numbers were at nearly 600 cases making it the largest outbreak in history. I mentioned that I was surprised out how little press coverage this was getting. By June that had changed, and there were well over 1000 confirmed cases spread over three countries. It had already reached many major metropolitan areas in Western Africa.
Perhaps the fear of economic collapse, Syrian red lines or the lack of control of our southern border distracted us. For whatever reason we ignored it. The short answer to containment is that we (America), who has the resources and capacity to move the needle during events like this, simply had other things on our mind. By the time we responded, it was too late to concentrate enough resources to contain the outbreak. The World Health Organization, Doctors without Borders and a few Charity organizations did what they could, but with out major western government funding and support, their ability is limited. The delayed response certainly played a role, but it is not the only factor in this unprecedented outbreak.
The proximity of this outbreak to the capital city of Conakry is also something relatively unique in comparison to other outbreaks of the disease. That access to major population centers, and the difficulty of effective quarantine in highly populated areas is what really accelerated the spread of this outbreak. At this point containment is highly unlikely, and it will take education, substantial effort and resources to simply keep a lid on it. That will not do it. In this case mass production of supportive therapies and vaccines will probably be what it takes to end this outbreak completely.
Should you be worried about Ebola?
As horrible as the disease is, it does provide some positive traits in its symptomology that provide us with the ability to limit the effectiveness of its transmission. This is especially true in well-educated populations like we tend to have here in the United States. Fever is generally the indicator for most westerners that it is irresponsible for them to expose others to what ever they are suffering from. In rural Africa and less educated portions of the world, fever may be viewed as an opportunity for the local villagers to get together and perform a ritual cleansing to “cure” the victim – which may involve washing, bloodletting or other counter-productive strategies. Where superstition and ritualized medicine dominate local thinking, Ebola is prone to rapid transmission. Where education, and science prevails, it will have difficulty.
Yes, you absolutely should be worried about it, but not to the point of hysteria, and only because a very little prevention can reduce your already highly remote chances to almost no chance. Certainly when travelling, following sound hygiene habits and taking extra precautions are a prudent step. Remaining alert and avoiding anyone who appears to have a fever or an illness of any sort is probably a prudent measure and not just because of Ebola, but most flus and diseases in general. Becoming a compulsive hand washer, and taking a draconian approach to your children placing their fingers in their mouth, nose and eyes may be worth the future risk of giving them OCD. The sudden onset of a high fever would be a good reason to keep your family isolated from you and everything you have touched – and for calling an ambulance if you had good reason to believe you had been exposed to a symptomatic person.
The sudden on set of a high fever with no reason to believe you may have been exposed is a good reason to call your doctor and have them give you an educated opinion on what you may be suffering from. It is not a good reason to drive to the local ER and request that they quarantine you… Your chances of contracting Ebola in the United States is somewhere on the order of 1 in 75,000,000. Your chances of being killed in a car accident are about 1 in 108… So if you wake up with a fever, decide to panic and drive to the ER, obeying the speed limit and putting on your seat belt are far more likely to save your life. Lastly, there is very little the ER can do for you at the early stages. Don’t panic, call your doctor and get some guidance.
Will Ebola become airborne?
Ebola is an RNA virus which in short means it has about one mutation per replication. That is a relatively high rate compared to other virus types, and that generally make them efficient adapters to new environments. That is the bad news about Ebola and the mutation rate is what I have seen the media seem to focus on. The good news is the mutations that would have to occur to allow Ebola to survive airborne transmission and infect a new host are very substantial. First and foremost, while viruses mutate all the time, they very rarely change transmission mechanisms.
I see many references to influenza and to be quite frank, Influenza is nothing like Ebola, and is an absolutely ridiculous reference for comparison. It replicates differently, thrives in different tissues, has a very different infection mechanism and transmits very differently due to its adaptations. Were influenza as lethal as Ebola, it would not have to have as much variation in the strains because the hosts would not have survived long enough for all that to occur.
Ebola is highly unlikely to become airborne (and I have seen some pretty smart virologists go so far as to say it will NOT happen). First is the suitability of the virus. Ebola thrives in bats, It does not thrive in humans and most other animals, and in fact kills a high percentage of them (In this case nearly 50%). The time it has to adapt and replicate in an unsuitable host like humans is relatively small, because our immune system kills it or it kills us relatively quickly. This reduces its opportunity to mutate.
Ebola can barely survive in mucous which is where it would have to thrive in order to become airborne, and although it does live, it does not live there or in saliva for long. It does not efficiently infect hosts through nasal tissue, and it is primarily adapted to infect blood and tissue cells of other organs. If you were to snort Ebola infected blood, you would probably catch the disease, if you were to swab your nose with Ebola infected mucous, your chances would be much smaller – although I would not participate in that experiment.
To become an effective airborne virus it would have to thrive at this means of mechanical transmission. That would require significant mechanical adaptations that would most likely limit its effectiveness at its current means of transmission. (Yes it happened in Reston from pigs to monkeys, under laboratory conditions with a very low mortality rate from of the virus. That is not a good model for how the virus will perform in the wild – we can do all kinds of things in a lab that don’t happen in the real world).
Will it go airborne? Maybe, but almost all experts think probably not. I will not worry about airborne Ebola for a far more practical reason. If it does become airborne, we can’t do a damn thing about it, and assuming the mortality rate cannot be reduced, 50% of the human population will become extinct within a few years of that occurring. Those who survive will be left with the task or rebuilding human society. That is the reality of an efficient airborne infector with a 50% fatality rate. You can spend time worrying about something you cannot impact, or you can get on with your life.
Why can’t we just make more of the cure?
There are two products that appear to have been successful in providing supportive therapy in defeating the virus and a number of potential vaccine candidates that are being tested. ZMapp is the supportive therapy version that was used on the two infected U.S. health care providers. It does not kill the virus, it supports the human body until its own immune system can recover enough to overcome the virus itself. The production cycle for a course of treatment is extensive, expensive and not approved due to lack of testing… The U. S. government just recently put $25,000,000 in production and the process is started, however, the production process is estimated to be 6 months once the facilities are set up and functioning, which will be later this year.
Tekmira and Glaxo Smith Klien have produced vaccines that are undergoing testing along with a few global competitors. TekMira’s TKM- Ebloa was given to an American Missionary who has since been released from the Nebraska hospital where he recovered. The vaccine variety’s are in testing, however the production lead times are substantial. Effectively vaccines inject a sterile or dead version of the disease into a healthy host, which prompts the immune system to respond as it would to a live virus. Later when that person is exposed to a live virus, the immune system already has the antibodies in place to kill the virus.
The problem is, it’s not really that simple. We have infected healthy people with supposedly dead virus and been wrong, we have mutated virus and created new and more deadly strains and caused thousands of problems over the years of developing vaccines. While they are a future solution to this problem, they are also the most risky portions of the solution for us to attempt to shortcut. The fact is that they take time to develop. Once you develop one, you then have to figure how to mass-produce it. My guess is that vaccines will take a lot longer then 6 months to develop. We haven’t touched on the antiviral drugs and maybe one of those will be effective, but until we conduct controlled tests, we simply won’t know.
What to do about Ebola?
If you really want to do something out side of taking some everyday precautions, throw some money in the pharmaceutical market at the company you think most likely to develop a vaccine first. Do the research to make a half educated guess as to which one that will be. The effort of going over the material will make you one of the best educated Ebola experts in your neighborhood – and education and simple practical measures are key to keeping this thing under control. Who knows, you might even make some money! For my part, I am done shaking hands with strangers for the time being, I am intentionally developing the habit of washing my hands frequently and I am slapping my own hand every time I touch my face, my eye or my nose with our first washing my hands – in an attempt to break the habit. Beyond that, I am keeping and eye out for people who look sick and avoiding them.
I am not changing my travel plans to Atlanta and Phoenix next week for our travel security presentations – because there is no reasonable belief that I will be exposed to the virus. That said, you could not pay me enough to give that same presentation in Liberia. Use your head, modify your plans only if there is some substantial risk of exposure associated with your behavior and take some simple precautions. Ebola is nothing to panic about, but if we want to contain it, we cannot ignore either!
Stay informed and stay safe!
~ Patrick Henry
#ebola, #ebolaeducation, #ebolaprevention