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So it looks like I am going to say this twice. After my last post, there was some criticism, some critique, some helpful commentary . . . and some new information and disinformation on the topic. As a result - and because scientists should correct themselves when they are wrong - I am posting a revised, expanded and corrected post so that we get the most accurate, up-to-date and calm, evaluation of Ebola.
To start with, there are some TRULY HORRENDOUSLY IGNORANT comments being made about Ebola on social media and the internet. This blog was originally posted to STOP some of these posts, but yes, I needed to have some of the information corrected.
First and foremost, there has been criticism of my scientific credentials. To clarify, yes, I am a Neuroscientist - currently. That is what I do, and reflects only a part of my training. My degrees are in Physiology and Pharmacology and I obtained that training via a medical school curriculum. As a part of my formal coursework, I was trained in abnormal physiology and pathophysiology - i.e. disease. The pharmacology coursework covered many aspects of medications to combat disease - including antibiotics, antivirals, etc. Prior to my doctorate I worked for 2 years teaching microbiology. As a current medical school faculty member with research projects involving rodents to humans, I am current on Universal Precautions, receive yearly training in HIPAA, Blood-borne Pathogens, Patient Safety and Herpes B (If you think Ebola is scary, don't even ask about HrpB). So yes, I have valid credentials.
Many commenters reference The Hot Zone by Richard Preston. It's a good book. I read it . . . in 1994. It is nonfiction, a true story - but two things MUST be considered about the book: First, it was written to be a medical thriller - all events are true, but not all true events are included in the book. Second - it is dated. The book was published 20 years ago - and written at least 3-4 years previously. Much of what we now know about the Ebola/Marburg viruses was unknown in 1992 (when Preston wrote first wrote the story for New Yorker). Current knowledge of the virus draws heavily from the outbreaks in the Democratic Republic of Congo (DRC - formerly Zaire) in 1995, the smaller Gabon outbreak in 1994-1995, the ongoing outbreaks in Gabon 1994-2003, 1996 human-to-human secondary infection case in South Africa, the Cote d'Ivoire, Kikwit and , Sudan, Angola, Ugandan variants from 1994-2007.
My point is, if all people are basing their knowledge on is an out-dated, 20 year old medical thriller - that knowledge is at best incomplete.
For sources, I am using National Library of Medicine's PubMed Health (http://www.ncbi.nlm.nih.gov/pubmedhealth/PMH0002315/), MSDS online, which has a great compendium of Ebola facts (http://www.msdsonline.com/resources/msds-resources/free-safety-data-sheet-index/ebola-virus.aspx) and Harrison's Principles of Internal Medicine, 18th ed. (http://accessmedicine.mhmedical.com/content.aspx?bookid=331§ionid=40726956) - available online through libraries and usually found in university and med school libraries. By the way, Harrison's is THE TEXTBOOK on general medicine for medical school and medical reference. You can rent the current edition for about $50, the Kindle and New Hardback run close to $100, but the 17th Edition (valid 2008-2011) is about $30-$40 used.
Now - back to my original points.
1. [original] This is not Africa. We actually have fully-competent medical professionals in every metroplex, city, small town, and rural community who are trained to recognize illness. The reason Ebola is so deadly in Africa is that so many of the people who are sick get NO MEDICAL CARE!
[revised/extended] Case in point from Harrison's Principles of Internal Medicine regarding the Zaire/Sudan outbreak in 1976: "Both epidemics were associated with inter-human spread (particularly in the hospital setting) and the use of unsterilized needles and syringes—a common practice in developing-country hospitals. The epidemics dwindled as the clinics were closed and as persons in the endemic area increasingly shunned affected persons and avoided traditional burial practices." and regarding Ebola Zaire epidemic in 1994: "The epidemic smoldered until April, when intense nosocomial transmission forced closure of the hospitals; samples were finally sent to the laboratory for Ebola testing, which yielded positive results within a few hours. International assistance, with barrier nursing instruction and materials, was provided; nosocomial transmission ceased, hospitals reopened, and patients were segregated to prevent intra-familial spread. The last case was reported in June 1995."
Thus, it doesn't actually require full Biosafety Level IV just to stop the spread - simple hygiene is sufficient - and that is something which hospitals do normally. To wit: "In a 1996 episode, a physician exposed to Ebola-infected patients traveled to South Africa with a fever; a nurse who assisted in a cutdown on the physician developed Ebola hemorrhagic fever and died despite intensive care. The index patient was identified retrospectively on the basis of serum antibodies and virus isolation from semen. No additional cases arising from care of the primary or secondary case were detected, nor did any secondary cases follow care of an unsuspected Côte d′Ivoire Ebola case in Switzerland. Thus, distant transport of Ebola virus is an established risk, but limited nosocomial spread occurs under proper hygienic conditions."
2. [original] Medical care for a viral infection consists of rest, plenty of fluids and nutrients, treatment for fever, treatment for nausea-vomiting-diarrhea, treatment with anti-viral medications - i.e. medications specifically designed to interfere with viral replication. Given appropriate supportive treatment - the mortality rate of even Ebola goes way down from what it is in Africa - in other words, even country doctors are able to treat it.
[revised/extended] Again, it was pointed out that "even country doctors" can't handle Biosafety Level 4. However, the Biosafety protocols are generally in place for studying the laboratory research. Level 4 is specified due to the high mortality rate historically associated with the virus and the fact that it can be spread by aerosols. Aerosols are fluid droplets temporarily suspended in the air - i.e. coughs and sneezes. It should be noted, however, that the tracked secondary infection cases are almost all associated with direct body fluid contact - blood, sputum, vomitus, semen. Even the single known tertiary transfer case (the South African Nurse in 1996) had direct contact with a patient's blood.
Keep in mind that in many African societies, customs regarding the dead involved kissing the corpse and close contact with the body during burial preparations. Stopping that practice did as much to halt the outbreaks as implementing the "Western Standard of Care."
[Correction] I am also not making light of the effort required to keep a patient alive that has gone into end-stage disease. As a correction to what I said above, antiviral drugs don't work, but supportive therapy improves survivability. The main treatments are platelets and keeping blood volume elevated, because the primary cause of death is low blood pressure and NOT blood loss. Low blood pressure causes heart failure, lack of oxygen transport in the lungs, fluid buildup in the lungs, kidney failure fluid retention all through the body and eventually coma and organ failure. Supportive therapy is just that - keep the patient supported - their blood volume and blood pressure elevated, use dialysis techniques to reduce the fluid retention, platelets and clotting factors to reduce bleeding and let the cells of the body fight off the disease (not that it is not the "immune system" per se which counters the virus, but the infected cell's own mechanisms to block replication of the virus. In that respect, in western medicine it very likely will be the case that an Ebola/Marburg outbreak will be similar to other viruses in that among those with access to supportive care, the predominant fatalities will be the very young, elderly and immune compromised.
3. [original] Most airborne viruses are not lethal. The dozen or so "lethal" viruses all require some form of direct transfer through bodily fluids in order to infect a new patient. The reason for this is that what makes a virus deadly is how fast it multiplies - and what tissue it infects - in a human patient. That usually means the lungs, mucus, blood, organs - and that environment is hot (98.6 degrees F), moist (nearly 100% humidity) and full of soft cells. Air is not. Even Atlanta, Houston or Miami in the Summer does not reach those conditions.
[revised/extended] I will repeat - most truly airborne viruses aren't lethal. That doesn't mean they aren't dangerous, just that they are not associated with the high mortality of 1980's HIV, 1976 Ebola, Herpes B, etc.
Many comments here and on Facebook counter that American hospitals can't control nosocomial infections such as MRSA and norovirus - but there are some extremely significant differences in how those diseases vectors are spread and what they are sensitive to. Norwalk Virus (i.e. norovirus - for one nosocomial example) is eliminated by bleach and Betadine, but totally unaffected by "antibacterial" soaps, chlorhexidine gluconate and benzethonium chloride. Norovirus is present in feces, sputum and vomitus; it survives dry cool air, boiling water, ether, and acids, but to date it cannot be easily grown in cell culture.
The "filoviruses" of which Marburg, Ebola/Zaire, Ebola/Reston, etc. are members are susceptible to: bleach, alcohols, ethers, acids, lyes, lipid solvents (soaps), detergents, UV radiation, high temperature (60 degrees C) - they can survive drying if it is still in a cellular medium (dried blood) but on the whole, these viruses are extremely fragile compared to the types of viruses most commonly found in "hospital" infections.
So yes, the basic nursing principles of hand washing, masks, gloves, not sharing needles, and cleaning up body fluid spills will go a long way to containing an Ebola outbreak.
4. [original] In order to grow and multiply quickly in those conditions, viruses are adapted to live best in those conditions. That means the virus itself is actually quite fragile. It will not survive on a cool dry surface. Even in sputum (what you cough up) it will die in a few minutes exposure to air, and can be eliminated with alcohol wipes, dilute bleach, Lysol, or even just soap and water.
[correction] Ebola and Marburg will survive drying, but all known cases of dried viral survival involve drying virus-infected blood or tissues - in other words, the virus is in its preferred environment when dry - not isolated on a counter-top or doorknob.
5. [original] Viruses are not bacteria. The fact that Americans over-use antibiotics and there are resistant strains out there MEANS NOTHING to dealing with viruses. Presence or absence of TRICLOSAN in antibiotic soaps is MEANINGLESS. PUREL(tm) hand sanitizer works just fine - it's the alcohol that does the trick.
[revised/extended] I will repeat the list of disinfecting agents that will kill Ebola & Marburg virus (From http://www.msdsonline.com/resources/msds-resources/free-safety-data-sheet-index/ebola-virus.aspx): "Ebola virus is susceptible to sodium hypochlorite, lipid solvents, phenolic disinfectants, peracetic acid, methyl alcohol, ether, sodium deoxycholate, 2% glutaraldehyde, 0.25% Triton X-100, β-propiolactone, 3% acetic acid (pH 2.5), formaldehyde and paraformaldehyde, and detergents such as SDS." That means alcohol wipes, hand sanitizer, Lysol, Betadine, Chlorhexidine . . . even soap and water.
[original] U.S. Doctors do know how to deal with viral infections - see 1-5 above!
[revised/extended] I see no reason to change this assertion.
6. [original] Why are these patients going to Emory? Because Emory has a HOSPITAL. CDC and USAMRIID are RESEARCH institutions, not HOSPITALS. Hospitals have very effective infection control mechanisms in place. I run a research lab. I deal with lab animals. When I need to deal with human patients - I do so IN A HOSPITAL!
[revised/extended] I stand by the original statement. It is worth noting the following details of laboratory infection (from MSDS online): "One reported near-fatal case following a minute finger prick in an English laboratory (1976). A Swiss zoologist contracted Ebola virus after performing an autopsy on a chimpanzee in 1994. An incident in Germany in 2009 when a laboratory scientist pricked herself with a needle that had just been used to infect a mouse with Ebola, however infection has not be confirmed. Additional incidents were recorded in the US in 2004, and a fatal case in Russia in 2004. "
That's FIVE NAMED CASES . . . in 40 years! When coupled with the actual mortality due to Ebola/Marburg since the first outbreak in 1969 - less than 3000 total deaths - the risks of "casual" outbreak are extremely small.
7. [original] Yes, viruses have a high mutation rate. That is why we need new influenza vaccines each year. BUT! What mutates is the PROTEIN COAT around the viral DNA/RNA. Typically not the genes themselves. Thus, the virus is HIGHLY UNLIKELY to sudden become more lethal just in the course of infecting a few humans!
See, what happens is, a virus "particle" attaches to a cell. As stated above, a virus is genetic material wrapped in a glycoprotein capsule. When the proteins attach to a cell, the proteins stay on the outside and the DNA/RNA enters the cell and starts to replicate. The cell is "taken over" to make DNA/RNA copies and build more glycoprotein capsules. The viruses are assembled, the cell dies, ruptures and releases more virus. HOWEVER since the original glycoprotein coat does not enter the cell and has to be built from scratch by the infected cells, that coating is the most likely to mutate. When that happens, the coat MIGHT be more likely to attach to different types of cells - but more likely, all that happens is that the bodies existing antibodies (and vaccines) won't quite recognize the new coat. This slows down immunity, but doesn't stop it in its tracks.
[revised/extended] While all of the above is true - the specifics for Ebola/Marburg is that the antibodies in the human don't do a whole lot of good anyway. The glycoprotein coat appears to function in a way to disguise the virus or discourage immune responses. There's new evidence regarding the mutation rate of Ebola which I will cover below.
8. [original] Viruses tend to become LESS LETHAL as they mutate. This is exactly the principle used in producing vaccines - take a virus, grow it in a cellular medium where it can reproduce and mutate to its own content - then harvest the mutations that have gotten less "virulent" - it's called ATTENUATED VIRUS and is how most vaccines are created simply because THAT IS WHAT VIRUSES DO. A more lethal virus is so unlikely that most research labs artificially create substances rather than let nature run its course.
[revised/extended] Again, please understand that what I originally responded to was a person on a Facebook thread going on about how viruses rapidly mutate into more lethal forms once an epidemic starts. That just isn't true. Again, I'm not saying that viruses don't mutate - they do - they change hosts, targets, animal vectors and means of transmission - again, mainly via changes to the glycoprotein coat. Thus, while all of the above is true - the specifics for Ebola/Marburg is that the antibodies in the human don't do a whole lot of good anyway. The glycoprotein coat appears to function in a way to disguise the virus and blind the normal immune processes (which is what mutation affects anyway) or discourage immune responses, so mutation of those characteristics is somewhat meaningless. There's even new evidence regarding the supposed mutation of Ebola during outbreaks which I will cover below.
9. [original] Yes, a change in transmission CAN occur throughout the course of an epidemic - however, what epidemiologists tend to find is that the alternate form was there all along, but not recognized. It's the sort of thing that requires tens and hundreds of millions of infected to occur. That's why we get things like bird flu and swine flu because the virus developed in a species untreated. Then when they jump to humans - they don't really take hold unless the victims GET INEFFECTIVE MEDICAL CARE (see #1&2).
[revised/extended] Regarding mutations: A commenter in the prior post mentioned that Ebola virus quickly mutates to a less lethal but longer incubation form. This point still makes my case - that viruses are more likely to mutate to less severe forms in humans. It is the long incubation in an animal reservoir which results in the previously unknown "deadly mutations." My statement was made specifically to counter rumors to the effect of "viruses quickly mutate to more deadly forms in the course of an epidemic." In fact, the respondent mentioned a mutation from a 85% fatal, 1 week incubation to a 60% fatal, 2 week incubation form. I believe that this refers to the two different virus strains identified from the very start in the 1976 Zaire/Sudan outbreaks. The more lethal strain was discovered first - largely because of its shorter incubation, and the longer incubation strain was discovered second - but in fact, this was not a mutation during the outbreak but a very close proximity outbreak with two different strains which occurred in two locations. The emergence of different strains of a virus usually occurs as a result of incubation in animal vectors in between outbreaks - the mutation required to jump species accompanies the change in lethality, incubation, transmission, etc. It's why we have yearly updates to influenza and continually shift between avian, swine, etc. variants of the flu. The so-called "airborne" Ebola (Reston virus) likely hopped from pigs (not fatal) to monkeys (fatal) in the Philippines. When it emerged in a monkey colony in the U.S in 1989, it was totally non-lethal in humans. In fact, none of the humans in contact with the monkeys showed evidence of disease, and most showed no evidence of infection.
Here is where the information conveyed in The Hot Zone is counterproductive to current knowledge and public education: Since the emergence of Ebola Zaire in 1976, the actual mortality rate of the subsequent outbreaks has been ~50-60% - still with incubation periods of around 7-10 days (only very rarely is incubation as long as two weeks - and in fact, a patient lasting 12 days is likely to survive). Since discovery of Marburg virus in 1969, the total mortality from these viruses is about 3000 people - in 45 years! Thus The Hot Zone is out of date since most of the outbreaks in the past 20 years have had roughly two-thirds to one-half the mortality rate described in the book.
Of course it is still a deadly, scary disease! One chance in two of dying is not much of a comfort over a sure death - but outside of sub-Saharan Africa, the disease has been stopped in its tracks every time it has left the region.
10. [original - with correction in italics] For every parent who has had a sick child AND DIDN"T GET SICK or who has had a close family member with any number of viral infections WHO DIDN'T CONTRACT THE DISEASE - keep in mind that it is in fact VERY HARD for viruses to jump from human to human. The major examples that do are common cold viruses - and only because they are slightly more stable in air (and way more resistant to disinfection) - but even then, the transfer is still from bodily fluid exchange (sputum from sneezes and coughs).
[revised/extended] Keep in mind, also that any person who is so far along in the progress of the disease to be coughing up blood is unlikely to be traveling by air to the U.S. Yes, there is a person who got off a plane and collapsed soon after, but what the public does not understand is that it takes many virus particles being given off to improve the possibility to infect a new person with a disease. Duration of incubation is important because it takes time for enough viral particles to build up in blood and the internal bleeding is a very late stage symptom. When an Ebola victim is most contagious, they are not moving around!
[update] The woman on the flight that landed at Gatwick didn't die of Ebola but of "natural causes." There is speculation because of the fact she was defecating and vomiting as she got off the plane - but dysentery from drinking contaminated water (one of the contributing factors to poor medical care in Africa) could do exactly the same. What about the poor workers who have to clean up the mess in the plane? British Public Health officials descended on Gatwick and put in place protocols to handle the situation, the cleanup, and record the information for everyone that not only was aboard the plane but was in any way associated with the plane. From a military Medical Command worker: "Mind you that the airline industry has protocols in place for dealing with body fluids on a plane." Indeed they do. All human waste has to be treated as potentially infectious, irrespective of whether it was just the baby spitting up milk when burped.
Also, there is a reported case in New York in a person coming from West Africa. However, at this time, Mt. Sinai is reporting that they do not suspect Ebola in their patient. They are running the tests based on his recent travel to be sure.
[original] SIMPLE PRECAUTIONS protect any person coming in contact with a person infected with any viruses - wear a mask, avoid contact with bodily fluids, wear latex/nitrile/rubber gloves if you have to handle bodily fluids, disinfect hands and surfaces that may have come into contact with bodily fluids. Extend the "glove" concept to sexual activity and these few precautions are used to effectively prevent viruses from influenza to herpes.
[revised/extended] I suppose I am over-reaching here, but the point is that Western Civilization does not exhibit the types of practices that spread Ebola/Marburg in Africa.
Has it happened before? Sure - Black Plague, smallpox, Spanish influenza, AIDS. But this is not the Middle Ages, nor is it 1985! The American public is more aware, more sophisticated, and more capable of dealing with precautions. Could a pandemic take hold and swamp our health care system? Yes, conceivably - but is it going to be Ebola? Very unlikely. Ebola is scary, rumors are flying . . .
[original and still valid] KNOW THE FACTS! and stop perpetuating the rumors and fear-mongering.