W.H.O. Forecast for Ebola Worsens as Mortality Rate Rises | Hacker News Reader

W.H.O. Forecast for Ebola Worsens as Mortality Rate Rises

nytimes.com

102 pointsaaronbrethorst106 comments

Not stopping this outbreak with all the resources we have is running a massive natural experiment in how well adapted Ebola can become for efficient human-to-human transmission. As a zoonotic virus Ebola in its wild state is very unlikely to be optimised for human-to-human transmission. Every new case is increasing the chance that a new strain will arise that will be efficiently transmitted between people. I am not too keen to see how well adapted Ebola can become to humans.

There's already limited evidence that some transmission is occurring via atomized saliva/mucous. A truly airbone variant could cause a "get in your bunker and ride it out" kind of event.

Might as well start worrying about an airborne mutation of HIV while we're at it. Wouldn't start heading for the bunker just yet.

Yes Ebola can be transmitted that way, but it is an unlikely route. The way Ebola is constructed it is very unlikely to become airborne [1], but it could increase in natural reproductive efficiency (R0). We really have no idea of the R0 for Ebola right now as we don’t have the people on the ground recording what is happening in the community.

Ebola does not have to become airborne for it to be a problem. Polio is not airborne and it has a very high R0 (5 − 7). The difference is polio is adapted for human-to-human transmission while Ebola is very unlikely to be. I don’t want to find out how well adapted Ebola can become.

[1] Something that I have noticed about the discussion here is many people are unclear about what it mean for a virus to be “airborne” (this is not surprising since most people are not virologists). What airborne mean is that the virus is adapted to spreading via small mucosal droplets. The classic virus for this is rhinovirus (the most common cold virus). Rhinovirus infects the mucosal cells of the upper respiratory tract, it causes you to produce lots of mucus, it makes you sneeze a lot releasing this mucus in small droplets into the air, the virus is hardy enough to survive in the small mucosal droplets, and it doesn’t make you that ill so you still go to work where you can spread it around your co-workers. Doing all the things required the evolution of many interlocking adaptations in the Rhinovirus genome.

Ebola's infection mechanism is nothing like Rhinovirus. While in theory it is possible that Ebola could acquire all the adaptions required to be spread efficiently by small mucosal droplets, it is really unlikely as there are so many changes required. This is why most experts think it is unlikely that Ebola will become “airborne”.

Not everyone is convinced:

http://www.cidrap.umn.edu/news-perspective/2014/09/commentar...

Some health workers have been infected even though they were equipped with significant protection.

Clearly infection rates in unprotected populations would be non-trivial, even without the kind of mutation that would make Ebola as infectious as a rhinovirus.

Given that many public spaces in Western cities are more densely populated than equivalent spaces in Africa, and there are much greater numbers passing through them, I'm genuinely concerned this has the potential to blow up in a vey bad way.

I'm not heading for the hills yet, but if case numbers begin increasing I'm going to consider it seriously.

The linked article is making a nuanced claim in general about aerosol transmission in general, not a specific change in the structure of the Ebola virus.

I'm not a doctor or epidemiologist, but I think, as a matter of common sense, that there's a distinction between being an "airborne contagion" and being merely transmissible through saliva. We know that Ebola can be transmitted through saliva, but it does not cause any symptoms that would tend to aerosolize that saliva (coughing or sneezing).

This would mean that you're not at all likely to get Ebola if you just happen to stand near an infected person, but we will still occasionally hear of people who seem to have been infected "through the air." These, one would think, would tend to be healthcare workers since they see patients at their sickest and may be performing procedures (e.g. intubation) that aerosolize saliva.

Wasn't there strong circumstantial evidence that the Ebola Reston strain was spreading without any bodily contact? It was discovered in lab monkeys in Virgina and spread from room to room of monkeys without any direct contact between the monkeys. It's possible caretakers were spreading it, but it seemed more likely that the strain had gone airborne.

I've read there was monkey to human to monkey contact, and it's acknowledged there's the possibility that was a route.

IIRC the conclusion was that the air ducts were the only feasible infection vector

Spreading fear is a hobby for some people. Every single story on Ebola seems to be taken over by people who are:

a) ignorant of virology

b) enamoured of a multiply-debunked case "they've heard" that "might have" involved "airborne" transmission despite the massive unlikeliness of that

c) deeply, deeply fearful about the "possibility of Ebola becoming airborne"

and

d) have never once anywhere posted anything wittering fearfully about influenza becoming a deadly pandemic, which is so many orders of magnitude more likely it isn't funny.

The degree of cognitive failure exhibited by these fearful posters is saddening. There is no obvious reason for them posting their fears and disinformation.

I am far less concerned about fear being spread than ignorant “solutions” being spread. Things like proposing that closing the borders to people from west Africa will solve everything, that it is somehow's gods way of dealing with “overcrowding” and Ebola will only happen to “those people", etc. There is a real risk that we in the west will go into isolation mode and not do anything.

Usually the progression of most diseases is toward easier transmission but lower mortality rates. Viruses that kill their hosts have a hard time becoming endemic.

My prediction for Ebola is that it eventually becomes like norovirus (stomach flu): a common gastrointestinal ailment that is painful and inconvenient, but seldom lethal, and spreads easily through contaminated surfaces.

Firstly, this might happen over millions of years, but this is unlikely to occur anytime in the short term. Many viruses that have been in the human population for a long time have quite high death rates in immune naive populations (think of small pox as an example).

Secondly, the mechanism of transmission of Ebola is quite closely tied to the cause of death. To be transmitted it needs to turn you into a massive viral factory and then make you very “leaky” so the virus gets spilled out into the environment. Any mutations that decrease mortality are also likely to decrease the infectiousness of Ebola

Thirdly, Ebola is starting off from a very high death rate. Even if there was a major decrease in the mortality rate (say it only kill 5% instead of 50 to 75% people), it would still be a huge problem.

http://en.wikipedia.org/wiki/History_of_syphilis

"The first well-recorded European outbreak of what is now known as syphilis occurred in 1495 among French troops besieging Naples, Italy.[3] From this centre, the disease swept across Europe. As Jared Diamond describes it, "[W]hen syphilis was first definitely recorded in Europe in 1495, its pustules often covered the body from the head to the knees, caused flesh to fall from people's faces, and led to death within a few months." The disease then was much more lethal than it is today. Diamond concludes,"[B]y 1546, the disease had evolved into the disease with the symptoms so well known to us today."

It doesn't take millions of years for diseases to adapt.

Of course is doesn’t always take millions of years, but it can take millions of years and it is not something you should expect will happen quickly. Even in the case of syphilis it still took 50 years. The evolution of syphilis (to a slower disease course) is exactly what we should be most worried about happening with Ebola as it will then be more effectively spread - just because syphilis is not as quickly lethal as it once was it is not something that you want to catch and leave untreated.

People here are so inclined toward numbers that I fear people are latching basic reproduction rate (R0) without proper context. The transmissibility of a disease is not some kind of invariant property of the pathogen.

It's not meaningful to talk about the R0 of Ebola in any kind of historic sense. Jungle/rural outbreaks are going completely different from urban ones, and this is a very different outbreak than previous ones. Very simply, if you have a 100% transmissible disease and are in a sealed room with 0 people until the pathogen is gone, your R0 is zero. If you're in a room with 100 people, it's 100.

I guess I'm saying that I'd love a reliable citation for your claim. Changes in R0 aren't necessarily evidence of that, and those claims (especially airborne transmission) is just needlessly and baselessly worrying people.

As others have pointed out, Ebola lacks a large number of important features that rhinoviruses, for example, have. It is possible given sufficient time Ebola will mutate in ways that generate those features. It is also possible, given sufficient time, Ebola will mutate into flesh-eating flying monkeys (admittedly, this is marginally less likely than becoming airborne.)

Viruses--parasite and pathogens generally-are incredibly narrowly adapted to their preferred mode of attack. They have to be, because the chinks in the host's immune system are almost by definition incredibly narrow. If they weren't the host species would not have survived.

This gives pathogens and parasites very little room to maneuver. They can't just arbitrarily bolt on new capabilities. They have relatively little genetic material to work with: 19 kilobases in the case of Ebola, which is less than the coding length of the majority of human genes (which can run comfortably into the hundreds of kilobases).

So think of Ebola like an evil eight-bit micro-controller. It's only got 256 bytes to work with. It has been carefully programmed with a tiny attack program that depends on a very specific weakness in the target system that requires it be plugged into a USB port controlled by a particular chipset rev from a particular manufacturer. The claim "it might go airborne" is equivalent to the claim that such a chip, under millions of random mutations, might be able to infect systems via network ports while remaining the same in every other respect.

This is not (provably) impossible, but it is of such low probability that I'm pretty sure anyone concerned about it should be in a state of panic regarding cows, coconuts, coronal mass ejections, and other far-more-probable causes of death if they want to make any claims to intellectual consistency.

My total layman's impression of this has been that it doesn't matter if the virus mutates to something "worse" -- that, short of some currently politically impossible action several orders of magnitude beyond what is currently being done, there is no really solid, non-magical-thinking, reason to believe this outbreak won't kill tens/hundreds of millions of people and threaten world civilization as we know it, even with the virus as it currently is.

The way the narrative has shifted in the past week has done a really good job of discrediting any routes to denial I'd previously had.

I would love to hear some credibly informed people disabuse me of this notion, in some way beyond calling my impressions those of an ignorant, panicky fool.

I am bouncing back and forth between the positions you describe. At the end of the day, though, if the "R-naught" is less than 2 in uncontrolled situations, and something like 1 in a hospital, it seems like it can be reduced to <1 pretty easily.

As I understand it, the most dangerous type of "worse" is ebola becoming less deadly.

> becoming less deadly

I suppose you could describe being contagious for longer or being contagious with less prominent symptoms as "less deadly".

While I am firmly on the side that believes that Ebola is very serious and we need to do everything we can to stop it [1], it is possible the R0 could drop below 1 via changes in behaviour of the people in west Africa. Since we really have a poor idea of what factors are driving the spread of Ebola, it is possible that these factors could change spontaneously. For example, people might get so scared of Ebola in the affected countries that people just stop caring for the sick and throw them out on the street to die. This might be enough to get the R0 below 1 and the disease will burns itself out.

The problem is hoping for a spontaneous change in behaviour that gets the R0 below 1 is like have a small fire that has started in the corner of your living room. Sure the fire might go out on its own, but is wise to sit there doing nothing just because it might go out?

[1] http://www.tillett.info/2014/10/08/ebola-what-needs-to-be-do...

In your piece, you advocate a military response. What do you want militaries to do to combat this problem? I'm terrified of this becoming a shooting war in which people suffering such horrible misery also become victims of violence intended to keep them "away."

I don't want tens of thousands in west Africa to die of ebola, but I certain don't want them to die lonely, thirsty, and ducking for cover. :-(

It seems like the most important tactic for reducing the R0 to <1 is building isolation treatment centers, yes?

I should write a follow up piece explaining why a military response, but the basic reasons are:

1. The scale of the problem is too large (both geographically and in the numbers of people affected) for any organisation (or group of organisations) other than the military to handle. Even if we moved to immediate mobilisation today it would still take months to get up and running on the ground by which time the problem will be vastly bigger.

2. We need to enforce a effective quarantine in the area and provide protection for the health care personnel. Only the military has the ability to do this.

3. I think we will have problems recruiting enough volunteer medical staff and may need to conscript them to get them to go.

4. Only full-scale mobilisation will stop the political games. Only if this problem is treated as war will we be able to get effective action out of the bickering political parties.

The military is quite good at operations 'other than war'. I was a minor cog in one effort, in 1991: Joint Task Force Sea Angel.

Details are searchable, but the upshot is that NGOs (I no longer recall if the term was used then) provided far more disaster relief assets and supplies, than the military did.

What the Marines brought to the party was command and control, and the ability to field, and support, a thousand guys in only days for delivering food, water, and medical aid.

And also, one shouldn't underestimate the ability of a brigade of disciplined troops to control masses of infected people. If they're told 'don't shoot' then they won't shoot.

That is already happening. There are already 565 US military in the region, and Obama plans to deploy up to 4000.

http://www.nbcnews.com/storyline/ebola-virus-outbreak/anothe...

Which is way less than the number we need there right now let alone in a couple of months it will take these troops to all get there.

If people want to know what it is like on the ground have a read of this blog post [1].

[1] http://pfmhcolumbia.wordpress.com/2014/10/12/les-roberts-the...

Honestly I have been disappointed by how effective they have been. I would expect the Army to be able to build field hospitals faster than this. There have been a lot of setbacks, detailed in a recent NYTimes article: http://www.nytimes.com/2014/10/03/us/us-effort-in-liberia-ba...

" the local contractor announced that the crusher’s engine, needed to smash rocks, had broken" and "Hauling parts and equipment from the United States and Europe takes time, and then there are negotiations with local contractors for heavy equipment."

That's crazy. The Seebees and other military engineers have rock crushers, and construction equipment. They know how to break that stuff down and put it on airplanes. The Air Force is used to transporting that stuff.

Now, I was only a stupid jarhead, and there may be issues not called out in the article, but I'd expect a week, tops, could get engineers on site, working, with their own equipment.

replying to you since i can't reply to the child reply i wanted to address.

If they deployed the SeaBees this wouldn't be happening. The key word is 'contractor', by using companies to avoid the political taint of 'getting involved where they aren't wanted' or being accused of 'wasting money' we send the proverbial 'lowest bidder' instead of the trained experts. Sad but true.

The linked article is now slow to load, for me. But I recall that the fellow who was having issues with the rock crusher was called out as a Seebee.

Perhaps he's there as sort of general contractor, working with the locals to build stuff, and not part of a battalion.

Which seems stupid, to me. Building a lot of stuff on short notice, as a team, is what the Seebee battalions are for.

"For example, people might get so scared of Ebola in the affected countries ... and throw them out on the street to die."

That might make it worse. In Africa, the distance between the gutter and the water supply isn't very far nor clearly defined (bad water causes a lot of deaths in Africa already). And given that the Ebola virus causes people to literately leak, dropping them in the street may containment local water supplies. Plus, the Ebola virus can probably survive in wet but dead tissue a lot longer than in the open area. So each one of these bodies would become a mini bio hazard, until the tissue decays to the point that the virus dies.

>That might make it worse.

Of course. I was just trying to give a concrete example of a change that might cause the R0 to drop below 1. It would be great if the R0 did drop below 1 on its own, but planning on this is not any wiser than hoping the small fire in the corner will go out on its own.

Very few articles about airborne mutation seem to bring up that ebola is an RNA-based virus, which means that it mutates at a faster rate and is less genetically stable than DNA-based viruses, bacteria, or most other pathogens. I wrote an explanation about the significance of RNA here: http://www.thinkhardly.com/think-hardly/ebola-for-entreprene...

I'm worried about the coming flu season. Many people will have the early symptoms shared by both flu and ebola (a fever and a headache). The medical establishment will need to find needles in the haystack.

Don't skip the flu shot this (or any) year, folks.

I've never gotten the flu shot, and hadn't planned to this year. I'm in great health; my immune system seems to be functioning extremely well. I never get sick.

However, I am concerned about the needle-haystack phenomenon with ebola.

Can you link me to a reasonable, digestible abstract about the real pros-and-cons of flu shot?

Is your immune system unusually effective, or do you simply have a lower exposure because people you come in contact with get their vaccines?

I surmise that I just have a good immune system (I'm not sure if it's "unusually" good). I don't go around asking all my friends and colleagues if they've gotten a flu shot, but I don't think they do?

edit: Jeez, downvotes? Did I say something wrong? I'm not trying to troll, just answering the question.

It's called being an asymptomatic carrier look up Typhoid Mary.

You may be infecting elderly and babies but are unaffected, as others have said a flu shot isn't so much about protecting you it's about people around you. My 70 year-old dad has IPF his lungs are shot and if he catches the flu he's as good as dead.

It's frustrating the ambivalence or apathy or just outright paranoia is so prevalent these days. At my workplace out of 400 people one year only 3 people got a flu shot; myself and two others. The majority are 20-somethings and others who don't get the concept of a vaccines.

I feel like saying "We don't care about just you we care about everyone!" but it's not a very good catch phrase.

Unfortunately, given the minuscule coverage compared to what's needed for good herd immunity, approximately 134.5 million doses distributed last year, and 100 million so far this year (http://www.cdc.gov/flu/professionals/vaccination/vaccinesupp...), while your advocacy doesn't hurt, how well can you ring fence your father? (As in get all the people he comes into contact with inoculated.)

But if you actually grant the "good immune system" bit, then wouldn't that imply that the immune system already is prepared to fight off the flu, or learns so very quickly; and then what ultimaltey is the difference between someone who was vaccinated with a syringe, and someone who was "vaccinated" by an actual infection, if you know what I mean?

Several days of shedding virus. Also, with influenza, you start spreading virus before you have symptoms. So keeping away from people once you notice you are sick isn't enough.

Healthy people with healthy immune systems aren't supposed to get the flu shot to prevent themselves from getting sick. They're supposed to get it because it drastically reduces the chances of passing the virus to at risk populations (who would have a much harder time fighting the virus than you). There are almost a quarter of a million hospitalizations due to the flu in the U.S. each year.

And while the number of deaths varies each season, the CDC estimates that the flu kills a minimum of 3,000 people in the US each year. Just to put this Ebola thing in perspective.

Current Flu shots have few side effects, and decent protection. I believe there is a chance of mild flu-like symptoms, a chance of ache near the injection site for a day or two.

The CDC has changed stances to recommend everyone (over 6 months) get a flu shot every season.

The CDC has a good rundown: http://www.cdc.gov/flu/about/qa/flushot.htm

The injected flu shot has completely inactivated (colloquially, dead) virus and cannot cause flu like symptoms. Recent formulation removed the egg allergy restrictions as well. There's effectively no reason for anyone to avoid being vaccinated.

My understanding has always been that since the dead virus works by triggering an immune response, 'symptoms' (that are actually part of the immune response, e.g. fever, soreness) can still occur, though they end quickly, as the body easily 'beats' the non-reproducing virus. Is this not the case?

Regardless, a person with nothing to fear from the flu getting the shot anyhow and having a fever for a few hours sounds like a cakewalk compared to what happens if they don't and infect me, even through my vaccination: I am very asthmatic and the flu for me can easily turn into months of bronchitis, or -- even worse -- pneumonia and hospital trips.

People like me rely on herd immunity to supplement our own vaccinations. Please get vaccinated.

It's easiest to just go straight to the source for this info: http://www.cdc.gov/flu/professionals/vaccination/vaccine_saf...

The two key points:

1. "The most frequent reactions reported after vaccination in children and adults are pain and other injection-site reactions. Up to 64% of people vaccinated with IIV experience pain at the injection site, which usually resolves in <2 days without treatment."

2. "Fever, malaise, myalgia, and other systemic symptoms that can occur after vaccination with IIV most often affect persons who have had no previous exposure to the influenza virus antigens in the vaccine (e.g., young children). In adults the rate of having these events is similar after IIV and after a placebo injection."

So other than your arm aching for <2 days where injected, the 'symptoms' are no more common than a placebo injection.

The "symptoms" are a nocebo effect, or just that people usually get the shot around the same time that they got the flu anyway. The idea that you somehow get a weak version of the flu is a misconception.

Asthma: Please look into Magnesium, Iodine, and if you're over weight do what you can about that too. These things did wonders for my asthma. YMMV of course.

http://theincidentaleconomist.com/wordpress/healthcare-triag...

I was young and in good health when during one semester of law school, I caught the flu during finals week. All the studying I had done all semester to learn the material was very hard to drag out of my brain while I was worn out and sore and barely able to breathe from the flu. Since then, I have received the flu shot most years, and I can keep productive during the winter while other people have to take time off from work to recover from a case of the flu.

As other comments have said, the main reason for healthy young people to take flu shots is to limit spread of the disease to people who will die from the flu or who cannot take flu shots. But you may very well get direct benefit for yourself, and the risk is very small.

http://www.cdc.gov/flu/protect/keyfacts.htm

http://www.cdc.gov/flu/protect/whoshouldvax.htm

Got swine flu just before my property final (thankfully, the others were over). Word.

I have never gotten a flu shot in my life. The last time I remember having the flu was over 10 years ago ... actually, the last time I can remember actually being diagnosed with the flu was on the day before going to first grade. So make that 20 years ago.

Do those shots really do anything much?

edit: the last time I had a serious viral sickness it was a combination viral and bacterial angina (mononucleosis combined with a normal angina) and that was about 8 years ago.

They handed them out at one of my previous jobs (corporate gig). Everyone that went for them came down with a mild flu after the shot and then proceeded to catch every other flu that came around during the winter.

edit: I hadn't realised sharing experience was such a downvotable offence... note I observed this over 3 years. Obviously the flu jab targets specific strains of flu, if the jab you get doesn't target the strains that happen to come round that winter then it's not going to help at all. I've no idea how well they can predict which strains will be in circulation but in my experience, not very well.

Don't listen to this guy.

Get your flu shot.

It's impossible to get the flu from a flu shot.

ollysb didn't say that anyone got the flu from a flu shot.

Yes, they did. "Everyone that went for them came down with a mild flu after the shot."

Post hoc ergo propter hoc

> then proceeded to catch every other flu that came around during the winter

There's generally only one or two flus in a season. Flu is often confused with colds and gastroenteritis by lay people - most of the time when someone says they got a "stomach flu" it's nothing of the sort.

This is why "sharing experience" is bullshit, especially when there's an entire global network of health organizations providing actual, data-driven analysis that shows your professed experiences to not be an accurate representation.

They raise your antibody serum levels so you are better able to fight live virus.

Yes I understand how vaccines work. But it just doesn't seem like seasonal flu ever gets in contact with me. At worst I will get a mild seasonal cold[1], which isn't problematic at all.

And I don't seem to get sick even when I make out with people suffering from a cold (like my girlfriend). Maybe I just have an abnormally strong immune system?

And while you could make a point of herd immunity, flu shots aren't very popular where I'm from. I only know of one person who's ever gotten one. The others either aren't getting them or our conversations don't steer in that direction.

[1] a bit of sniffles, some coughing, no fever or headaches

The flu vaccine is a bit of guesswork since, as I understand it, they have to pick a strain or family of the virus to vaccinate against, based on which they think is likely to be popular that season. They can be wrong.

See reply here for why healthy people should still get a flu shot

https://news.ycombinator.com/item?id=8456067

Or I could just avoid touching people if I have the sniffles? And just follow standard recommended practices for limiting the spread of colds (wash hands before/after touching face, only sneeze/cough into your elbow, avoid sick people etc.)

Does that not suffice? Can I still transfer the flu even if the virus isn't affecting me in even the slightest possible way?

Well, define "suffice." The methods you list are certainly good things to do, but you you really think that would make it impossible (or even very unlikely) for you to infect someone else? When you sneeze into your elbow, no droplets at all escape into the air? Do you always wash your hands after sneezing or touching your face before touching any other surface? I seriously doubt it.

Meanwhile, what are the risks of getting a flu shot? Effectively zero.

Just get it, please.

> Meanwhile, what are the risks of getting a flu shot? Effectively zero.

To be perfectly honest, it's not about risk. It's about the nuisance of yet another errand to run. Unfortunately that small-ish barrier is often enough to prevent me from doing things that don't feel absolutely essential.

Hell, I wonder where I would even go to get a flu shot ... my general physician? I don't even know where their offices are ...

Many drug stores are doing it now. Check out Walgreen's, CVS, also Target.

Heck, my GP told me to go to one to get my Tetanus etc. booster (it's a lot easier for them to keep it in stock).

I relate. I usually don't get one either for equally poor reasons. But these days they make it really easy: you can get one from CVS, Walgreens, Rite Aid, and other pharmacy chains.

At least in NYC, you can walk into any pharmacy at any hour of the day and get it for free in under 5 minutes. I know because I walked into the Duane Reade next to my building at 10pm on a Saturday and got it. It takes longer to buy a 6 pack of beer, then you at least have to take out ID.

> Like my girlfriend.

If you regularly make out with said girlfriend, I'd be fairly confident that either of you would have a difficult time making the other ill.

I hadn't gotten the flu for over a decade without getting flu shots. Then at age 23, I got it and couldn't leave my apartment for several days. Prior to that, I didn't really understand how someone who wasn't old and decrepit could feel too weak to go outside. I would read it in books, and it made no sense to me.

I share these worries.

In addition, consider some of the potential social effects of flu season. You're on a crowded international flight and a handful of people are clearly ill. What are the odds someone on that plane freaks out about Ebola?

I'm trying to remain calm about this, but its growing increasingly difficult.

We're not far off pandemic territory. 10k new cases per week?

Very very alarming.

I'm really interested to see if the r-naught is sustainable in developed countries. This paper (http://www.eurosurveillance.org/ViewArticle.aspx?ArticleId=2...) projects it as between 1.0 and 2.0 -- the nurse in Dallas makes it at least 1 for the first US case, but it could be a few more weeks to know if she was the only one.

>Our statistical analysis of the reproduction number of EVD in West Africa has demonstrated that the continuous growth of cases from June to August 2014 signalled a major epidemic, which is in line with estimates of the Rt above 1.0. Moreover, the timing of Rt reaching levels above one is in line with a concomitant surge in cases in Sierra Leone and Liberia. In a worst-case hypothetical scenario, should the outbreak continue with recent trends, the case burden could gain an additional 77,181 to 277,124 cases by the end of 2014.

Not good. R~2 is a deeply scary figure. R1.7 is better but still wildly explosive. 1.4 puts us in run of the mill "ballooning epidemic" territory.

The best case estimates of R-naught for Africa don't have a whole lot of "best" about them.

Clearly the dataset outside Africa isn't large enough to support meaningful analysis yet. I hope it stays that way, and Africa can get its arms around this thing before it kills millions.

For others who wondered about the R-naught reference - how many people one infected person will then onwards infect.

http://en.m.wikipedia.org/wiki/Basic_reproduction_number

Measles is 12-18, Ebola 1-2. Before that makes you feel comforted, 1918 flu had r0 of 2-3.

Great.

Problem is, the data from West Africa is so bad in quality it could easily be 3 (e.g. I believe that's in line with the CDC's worst case estimate for January).

Which to echo simplemath is deeply scary.

> the nurse in Dallas makes it at least 1 for the first US case, but it could be a few more weeks to know if she was the only one.

Since it's a single case though, this is far from statistically significant. We don't know what R0 will be in the US.

Malaria kills over half a million people a year, out of over 200M cases. Why is ebola so much more alarming?

A few reasons.

1) Because malaria is 'over there' and ebola is threatening to come 'over here.'

2) Ebola has been hyper sensationalized, and is not as well understood as malaria.

3) Ebola has a very high mortality rate, with an almost coin-flip chance of surviving it.

4) The world has been dealing with malaria for a very long time. Ebola is new on the block. It seems any new virus tends to make waves these days, from SARS to West Nile.

You pretty much answered your own question- .5M deaths out of 200M. Ebola kills 50-90%

I think the answer can be summarized: "human-to-human" transmission. Malaria, to be sure, has been a much more significant public health problem historically, but with ebola you have the possibility of human-to-human transmission and, thus, geometric growth. You also have the possibility that it will spread elsewhere in the world. And we're not just talking about the western world here either (though that surely drives more than its fair share of the panic). Imagine, for instance, ebola in Mumbai or Mexico City.

Uncertainty is really the kicker. Ebola may turn out to be substantially less significant than malaria. But we can't rule out it being a good deal worse.

Malaria is mosquito-borne; effectively a condition of geography. One moves to a non-malaria zone and is no longer susceptible; or one can invest in some mosquito netting and dramatically cut their risk. Caring for the infected or burying the dead does not increase the risk.

Ebola is person-to-person and by all accounts highly infectious, particularly targeting caregivers. It's a recipe for a much more severe social breakdown.

It's also clear the number of malaria cases is bounded, at a level that is in some sense "livable". It is not clear at what level Ebola will top out at; it may not be compatible with maintaining a functioning society in particularly hard-hit areas.

You can easily protect against Malaria with various drugs.

Donation link:

http://www.doctorswithoutborders.org/our-work/medical-issues...

I've been following this organization for a few years now. Its blogs and 'field news' have informed me about places in the world I didn't realize even exist - places with unique cultures that are threatened by lack of medical care and all the ways in which war and capricious borders create shortages in supply of medical care.

I've given what I can - please do the same everyone!

Dr. Paul Farmer discusses Ebola: http://youtu.be/lb11QbP3tOg

After listening to the talk, I'm not as worried as this article makes me. I certainly trust the source in the video better.

If anyone is interested I have put up a post on my personal blog about Ebola and what needs to be done [1].

[1] http://www.tillett.info/2014/10/08/ebola-what-needs-to-be-do...

There are a lot of great perspectives and threads in this discussion. If you're interested and want to develop them further, a few of us have stood up ebola-wiki.com to share data sources and information. It's a place to build on these ideas, cite your sources, and refine them. I'd welcome feedback. Also, if you are a mediawiki admin please contact me. We could use more help and advice as this scales.

What scares me the most is the mortality rate. The numbers right now put it at 50%.

Catch Ebola. Flip a coin and guess heads or tails. If you guess incorrectly, you die.

It will be interesting to see this number once it (inevitably) spreads to "developed" nations with much higher standards of health care.

If Ebola does become able to spread in western countries (right now it can’t), then unless you are one of the first few hundred to get it then there will be little difference between the first world and third world since all our hospitals would soon collapse.

> What scares me the most is the mortality rate. The numbers right now put it at 50%.

Unfortunately, it's actually worse than that.

The initial predictions about this outbreak were a 50% mortality rate, later estimations put the rate at closer to 70%. To continue your metaphor; You flip two coins and try to guess heads or tails. If you're wrong on either coin, you die.

[1] - http://www.aljazeera.com/news/africa/2014/10/ebola-outbreak-...

There is a good recent article in The Guardian where three western nurses describe their experience in caring for people with the virus.

http://www.theguardian.com/world/2014/oct/13/ebola-nurses-de...

This seemed misguided:

"I have heard media reports calling for people such as me who have been treating Ebola patients to be quarantined for 21 or even 42 days. These ideas are not based on the medical facts. People only need to be quarantined if they are showing symptoms and if you do not have a fever, there is no risk of you transmitting Ebola to someone.:

What happens once you start showing symptoms? They're likely to have touched a large number of surfaces and interacted with a large number of people by the time they realize their worsening condition is the onset of Ebola. By the time I know I'm sick, I'm pretty sick. I'm damn good at trudging on until the point of no return and I'm sure healthcare workers would do the same since Ebola is contagious well before it's debilitating.

"These ideas are not based on the medical facts. People only need to be quarantined if they are showing symptoms and if you do not have a fever, there is no risk of you transmitting Ebola to someone."

Also, that above fact is wrong. "Yet the largest study of the current outbreak found that in nearly 13% of "confirmed and probable" cases in Liberia, Sierra Leone, Guinea and elsewhere, those infected did not have fevers." http://www.latimes.com/nation/la-na-1012-ebola-fever-2014101...

Even letting one-in-ten get through undetected is too high. Especially since any strains of the virus that are harder to detect are exactly the strains that most the most threat and must be kept out.

why is USA still allowing people from those countries fly in? the body temperature measure at airport is 99% useless.

When will Duncun's family pay back all those medical expenses here since he lied to the airport before he boarded? Not to mention he put other innocent people in ciritical danger at Dallas.

I'm sorry, did Duncan's FAMILY lie on the form? While we're at it, did Duncan? It's fairly widely reported that he did not know that the woman he helped had ebola. Apparently her family had been in denial, and told people she was experiencing complications from the pregnancy.

>Duncan did not know he'd been exposed to Ebola by the pregnant woman, says his brother-in-law, John Lewis.

>"The family said that the girl did not die from Ebola; they continued to say it until they went and buried this girl," says Lewis.

http://www.npr.org/blogs/goatsandsoda/2014/10/09/354645983/f...

And in any case: how about you spend a little more time trying to feel compassion for people like you who just lost a husband/father/son and a little less trying to figure out who should get the bill.

> "It's fairly widely reported that he did not know that the woman he helped had ebola. Apparently her family had been in denial, and told people she was experiencing complications from the pregnancy."

She apparently died several hours later. If that is true, then while he was interacting with her she was extremely symptomatic. We're talking bleeding out of everywhere. Ebola is not a subtle disease, and she was not merely exhibiting flu-like symptoms at that point. Furthermore, the hospital turned her away because their ebola ward was full.

While it is possible that he was an idiot who believed the claims that it was simply pregnancy complications, we're deep into "sufficiently advanced incompetence is indistinguishable from malice" territory. And frankly, it is more charitable to Duncan to assume that he lied. Better a liar than an idiot of that magnitude.

http://en.wikipedia.org/wiki/Thomas_Eric_Duncan#Timeline_of_...

> "On September 15, 2014, the family of Ebola virus disease patient Marthalene Williams were unable to summon an ambulance to transfer Williams to the hospital. Their tenant, Duncan, helped to transfer Williams by taxi to an Ebola treatment ward in Monrovia, Liberia. Duncan rode in the taxi to the treatment ward with Williams, her father, and her brother. The family was turned away due to lack of space and Duncan helped carry Williams from the taxi back into her home, where she died shortly afterwards.[11]"

Most Ebola patients never bleed profusely the way we imagine them to (though, as it happened, this particular woman was bleeding from the mouth). It apparently is actually very hard to distinguish from other tropical diseases in most cases. http://www.who.int/mediacentre/factsheets/fs103/en/

In fact, that is why it took so long to identify and respond to the current outbreak.

>Here, then, still in January, long before the outbreak took off, a team of doctors stood at ground zero, staring at some of the first casualties. They had no idea what they were looking at.

> The way Ebola kills would seem impossible to mistake. What the casual observer knows of Ebola are its most spectacular cases, or the cinematic depictions of them: prodigious bleeding from eyes, ears, nose, anus, and nipples. Symptoms like these, presenting all at once, would be impossible to miss or misinterpret. But not every Ebola case ends with such a biblical scourge, and many of Ebola’s symptoms are identical to those brought on by other diseases. Until its final stages, Ebola can easily be mistaken for cholera. It can also look a lot like malaria, another long-tenured killer in Guinea.

http://www.vanityfair.com/politics/2014/10/ebola-virus-epide...

I don't know why it's so hard to believe that the woman's parents, in denial, said that she was merely suffering from serious complications from her pregnancy and he believed them. It's not as though he would have conducted a thorough exam. He just helped the family carry her a short distance.

And, I should add, the very fact that he did this is probably the best evidence there could be that he did not know she had ebola.

Regardless, in this particular case it seems rather apparent that Duncan lied. If she was bleeding from the mouth and he was aware of it, in Liberia during an Ebola outbreak, then there at the very least he should have answered that "history of contact with ebola" question with a strong "maybe".

I am suspicious of the family being in denial, but I don't think that it is impossible. However for Duncan to also be in denial is far less probable.

It also should be noted that "I thought she had cholera/malaria" and "I thought she was having complications with her pregnancy" are two rather distinct claims. Had he said "I don't think that I had contact with ebola, but I did interact with somebody who seemed to have cholera recently..." then I would be far less critical.

Look, I don't say it was A-OK that Duncan checked "no" in the form. (Which, by the way, asks the question in several different forms, to try to capture cases where people were exposed to something, but don't know what to.) But I do wonder why people are so quick to demonize. He was not a highly educated person, he didn't know the woman he was helping and only saw her briefly, and was (or would have been, had he known) terrified of the consequences of checking "yes" on that box, both in terms of what the authorities would do down the line (quite possibly stick him in a decrepit hospital full of people dying of ebola) and what that would mean coming to grips with.

I'm also surprised that people so uncritically accept that his coming here was so terrible in any case. I would bet money that his dying in Dallas means he has infected far fewer people than if he had stayed in Liberia. It certainly serves our purposes to convince people that people with ebola should stay put but I've never heard it explained why, objectively, that is actually the case.

He likely did lie, but can you blame him? If you were faced with a question where answering truthfully meant you'd be trapped in a hellhole where what little healthcare infrastructure there was had already completely fallen apart, and lying meant access to world-class care... which would you pick?

Cheer up about the downmods: If it gets bad enough, your sentiment will be the universal one.

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