Liberia is experiencing a major Ebola outbreak.
Liberian President Ellen Johnson Sirleaf has announced the closure of most of the Ebola-hit country’s land borders after the deadly tropical virus spread to two of west Africa’s largest cities.
Liberia, along with neighbouring Guinea and Sierra Leone, is struggling to contain an epidemic that has infected some 1,200 people and left at least 670 dead across the region since the start of the year.
A 56% mortality rate is a great improvement over the 90% reported in previous outbreaks, but it’s dependent on getting care to the affected rapidly. And one of the affected is an American doctor working to treat Ebola patients in Monrovia. Even that rate could worsen if the medical infrastructure were to break down.
Report of plane passenger who later died of Ebola.
The latest news claims that the witch doctors are blaming western medical personnel for spreading the virus and the country people are refusing entry into their villages to government medical workers. When someone becomes ill, the villagers flee, dispersing to other villages and spreading the virus. This has all the looks of becoming a real plague. What happens in Lagos in the next month will tell the tale.
That is absolutely tragic. For me, it brings extra poignancy to the necessity of the work that secular activists are doing around the world.
What keeps this from turning into a uncontrollable epidemic? Dumb luck?
I did wonder, however, about some of the volunteers from the US. What kind of training do they get before heading into areas that may be affected?
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The american doctor who was infected was working for Samaritan’s Purse, Franklin Grahams charity org. There is another volunteer with them that is also infected.
What we really need now is some more unnecessary war.
Erlend Meyer, the virus is not as contagious as some (e.g. influenza and the common cold). One has to have pretty direct exposure to infected bodily fluids. There is also the fact that the mortality rate also tends to suppress transmission.
To my knowledge its the lethality, people die quickly making it more difficult to pass it on.
@7
Argh, I got sharked.
So, I guess we have to hope that this Ebola virus does not mutate into some less lethal, but more contagious form? Sh-h-h-hush, it may be listening to our thoughts!
Remember that guy with drug resistant TB who thought getting home was more important than quarantine? Someone’s gonna pull the same trick this time.
where or in which species does this virus reside in a less fetal way or is there any?
uncle frogy
unclefrogy: Last I heard, the primary suspects were bats.
I Fucking Love Science posted an article last week titled What Happens To Your Body When You Get Ebola?
It is a pretty nasty disease.
It seems to me that a lowering of the death rate might lead to this strain being more dangerous, since it will allow the 44% survivors to spread the disease four times further than the ~10% from the previous strains did. This is not good news.
Talking about not-good news, you’ve heard of the family that bust their sick relative out of the Sierra Leone hospital and took her home? She died. No word on the rest of the family yet.
I F-ing Love Science had an article last week, What Happens To Your Body When You Get Ebola?. It is a pretty nasty disease.
(Bah. I tried posting this three times before I realized there was an obscenity filter.)
I F* Love Science had an article last week, What Happens To Your Body When You Get Ebola?. It is a pretty nasty disease.
(Bah. I tried posting this three times before I realized there was an obscenity filter.)
Hmph. I’m trying to link to an article titled “What Happens To Your Body When You Get Ebola?” on the site I F* Love Science. Some kind of obscenity filter keeps blocking it. Maybe the bare link will work?
http://www.iflscience.com/health-and-medicine/what-happens-your-body-when-you-get-ebola
Hmph. I’m trying to link to an article titled “What Happens To Your Body When You Get Ebola?” on the site I F* Love Science. Some kind of obscenity filter keeps blocking it, even just the link.
Yes this is a bummer but keep in mind that more Africans die of other infectious diseases — malaria, TB, HIV, diarhheal diseases — by orders of magnitude. However, that isn’t news and we don’t pay attention to it.
Anyway:
The Ebola virus attacks T-lymphocyte cells, which are lynchpins of the cell-mediated immune system. HIV attacks a subset of these cells, but as a retrovirus, it kills them off slowly, over a matter of years. Ebola is a regular virus, and a very aggressive one at that. Ebola’s lethality is tied to the fact that some of these T-cells are also used by the humeral immune system. The difference between them is that cell-mediated immunity fights off larger threats, such as cancers, fungi, parasites, protozoa and the like while humeral immunity fights off viruses and bacteria using antibodies.
Ebola has an incubation period of one to three weeks, at which point the humeral immune system kicks in. For several days, the infected person goes through the worst symptoms of a massive viral infection: nausea, diarrhea, vomiting, fever, aches. These are all caused by the innate immune system, the first line of security which works to make the body inhospitable to pathogens.
If the humeral immune system is able to get a handle on the virus, the innate system begins to step down its efforts after a few days. The symptoms fade, and within a month or two the virus has dropped to undetectable levels. The virus is still contagious during this period, however, even if you are feeling completely recovered.
But because the virus has been destroying the T-cells used by the humeral immune system, most likely the attack will fail. With no other course of action, the innate system kicks into emergency overdrive, producing a flood of proteins called cytokines. One of their functions is to signal cells to be on very high alert. The only way a cell can fight off a virus is to commit suicide and thus prevent itself from being used as a virus factory. At this alert level, cells kill themselves very readily, for any reason that might be construed as a threat. This results in the lesions and organ failure that marks the terminal stages.
Studies suggest that Ebola is as contagious as influenza, with each infected person passing it to between two and four others. There are many viruses that are worse — one person with measles can spread it to 18 others — but it is bad enough to sustain a pandemic. The ONLY thing that seems to have prevent a global catastrophe is the fact that outbreaks typically occur in rural areas, with small populations having little contact with people in other areas. If it were to appear in a major urban center….
Gregory
Sometimes, the immune system seems to be this: http://tvtropes.org/pmwiki/pmwiki.php/Main/StopHelpingMe
I have read that the incubation period is from two to twenty-one days.
When is the disease actually transmissible, only after the onset of symptoms, or before that?
This could really get nasty.
@cervantes:
What? huh? Oohhhhhhh! I get it. You’re pretending that white people generally care about black Africans. Because those other diseases? Totally treatable or even curable with a good health system. So the joke is we’re not paying attention to Ebola only because we’re worried it might someday escape Africa and kill white people, but because we care about every preventable death, even those of black Africans?
That was totally a good one. You really had me at first.
@janiceintoronto:
yep. Only after onset of symptoms, but the initial symptoms are headache and then something similar to influenza. I’ve heard many say, “Influenza or cold” but it really doesn’t have (as I understand it and I could be wrong) the runny-nose type symptoms more characteristic of a cold, and *does* have the achy-ness characteristic of a flu. So I’d say flu.
If the person is not aware of previous exposure to Ebola, this similarity to a mild, every day infection makes people think that they can just power through it, and makes other people less worried about interactions that can pass the virus.
So, yes, not til symptoms, but **before** the symptoms that make it clear that this is something super-serious and not to be trifled with.
If one contacts Ebola and survives, do they then have any sort of immunity?
:::::: correction – contracts::::::::::::::
Any sort? Antibodies to Ebola are produced, yes.
But of course it’s more complicated than that. The descriptions that I’ve read aren’t scientific papers – I’m just not minimally competent to read actual virology research – but they describe part of the problem as the fast replication of filoviruses.
Now for the pure speculation: It’s possible that the prior existence of antibodies would be enough to prevent a new infection from getting out of hand, and thus render the disease non-lethal to someone previously exposed. Also, I have no idea how long the anti-bodies last in your system. Does the presence persist for 6 months? 10 years? A lifetime? Don’t know.
So the answer to your question must be qualified with:
Production of anti-bodies ≠ immunity.
Thanks, CD. That was my guess but I didn’t find any corroborating info in my google search and my rudimentary knowledge of the immune system dates way back to college anatomy class.
So if one is lucky enough to survive ebola, one may be able to contract it again. And we do not know if the antibodies produced would impart any protection. Ebola researchers really have their work cut out for them.
@ #7&8: Thanks, that’s what I expected. The average incubation period is reportedly 2 weeks, meaning it can’t be too contagious in that period. The quick progress of the disease and mortality rate would also limit the spread.
Scary stuff nonetheless, hope there’s some effective treatments in the works…
A pathogen needs to build up to sufficient levels before the immune system gets alerted. Thus, many viruses have a latency period, a phase between initial infection and the onset of symptoms during which time the virus is multiplying and spreading. Most rhinoviruses and adenoviruses (both of which cause colds) have a latency period of two to five days, for example.
Typically, a virus is not contagious during its latency period, as there just isn’t enough virus to spread.
The real threat for contagion comes after the symptoms begin to subside. Many symptoms of a viral infection are caused by the innate immune system trying to make the body inhospitable to pathogens. When the humeral system takes over, the innate system begins to power down. It can take one to three months before the viral load drops to undetectable, during which time the infected person does have enough viruses to spread it to others. If a person survives Ebola and, say, goes to work a few days after he’s feeling better, he is putting everyone in that office at great risk.
Fortunately, basic safety procedures — frequent hand washing, do not share utensils, cups or food, etc. — seem to be effective against Ebola. Unfortunately, many of these procedures are not followed for practical or cultural reasons. Clean water is in severely short supply in most of Africa, which makes hygiene practices we take for granted next to impossible, and the custom of putting a single plate in the middle of the table and everyone using their hands to serve themselves is very common.
One question I have not seen answered about this particular outbreak, which strain of Ebola is it – Marburg, Zaire. Reston or a new strain?
Or Sudan, you’re forgetting.
I read something a while back on how west African outbreaks had a viral strain more similar to Reston, but it obviously it wasn’t Reston as Reston was first found, since that Reston doesn’t cause significant pathology in humans.
But even if that was true of past outbreaks (that the virus was a variant of Reston, and I’m not guaranteeing that), the news from this outbreak is different.
NEJM has the details.
@Crip Dyke #24 – How long antibodies last depends on a lot of factors. Vaccine booster shots are required every 5 to 10 years, depending on the virus, so that is probably a good baseline. Some diseases like chickenpox are common enough that your immunity is kicked every couple of years just by being out and about, which keeps the antibodies in full production (remember, antibodies do not keep you from getting a virus, they help to fight it down before it can become a visible threat.)
But, there is the matter of varying strains. We need a new influenza vaccine every year because the virus mutates rapidly: the antibodies generated last year won’t be much use this year. I don’t know how quickly Ebola mutates, and it may be that one can survive Strain A only to fall to Strain B because A’s antibodies are unable to neutralize Strain B.
That’s a question that can be answered by people who actually know what they’re talking about.
This puts Ebola/Marburg in the same general area as Hep B/C. The rate of change is an order of magnitude smaller than HIV-1(a) or Influenza A. Both of those are known to be slippery, though, so Ebola/Marburg is probably more average in rate than slow, as one would expect if HIV & influenza were average.
I am not particularly plugging it but for a good general understanding of this and related viral infections and their history read “The Hot Zone”. At first it gives an impression of being overly dramatic – until
that is you read the last few chapters which recount an outbreak in imported research monkeys from
the Phillipines that occurred in Reston, VA. There was evidence in that instance of airborne transmission which would be a big step in the wrong direction.
Yes in the early reports I read it is stated that Fruit Bats which are popular as both food and pets are a
reservoir species for Ebola. Also of course primates. Also apparently some species of antelope and deer
and other animals that can be generally classified as ‘bush meat” i.e. hunted for food.
I have spent (more than two decades ago) a lot of time in these countries and it is fairly plain that they are among the least well equipped of any places on earth to deal with such a crisis. Communications outside major cities are primitive at best. Reserouces are very limited, especially medical resources.
I seriously doubt for example that something as simple as chlorine bleach is readily available outside
the major coastal cities of Liberia and Sierra Leone.
It has been said that it is relatively difficult to contract ebola but that depends enirely upon the type of
exposure. If you wonder at all why people are so afraid of this disease just read about its symptoms
and progression.
I am not a biologist and cannot speculate upon the effect on the rates of evolution of a virus and how they might be affected by a major outbreak with thousands of vicitims concentrated together. But I think the Reston example is a cautionary tale. In the right circumstances the virus might be capable of
becoming much more infectious should it become transmissible by aerosols.
Frankly, I was alarmed when I first heard it had appeared outside its traditional confines of east central
Africa to West Africa. How did that happen? For all I have been able to discover fruit bats are not in
general ‘migratory’.
To an earlier comment, why yes of course, we who are not subject to the haphazard realities of the so
called third world readily ignore the actuarial realities. And of course plenty of people die from more widespread diseases all the time.
Thanks are due the blog host for shining a light on this. We should pay attention and apply some of our
extravagant resources to doing something about it.
So far we have four fairly large cities involved. Lagos, Monrovia, Freetown and Conakry. As the book
cited above states in more dramatic terms, large populations are poetential food for the virus. We should be concerned. Very concerned.
What will happen when the first case of death from Ebola shows up in London or Paris?
How long before some mega-Christian personality starts spouting that this is God’s will, because the people in Africa once made a deal with the Devil or something like that. Then they’ll tell all the good Christians that if they pray real hard (and donate), they’ll be spared.
@CD
Yeah the Sudan virus, I forgot that one.
Checked out the references you gave, if its a variant of Zaire, then it certainly travelled a fair distance from the original infection area, unless it was transmitted by a person or a bat. That said it would appear that the fatality rate is fairly low (~45% or so). Which could either be a good or a bad thing, depending.
As for the Hot Zone, I think Prescott did overly dramatize things. Weirdly enough you drive by where the office park used to be – its a daycare now. A much better book written about the same time is Laurie Garrett’s The Coming Plague. http://www.amazon.com/The-Coming-Plague-Emerging-Diseases/dp/0140250913 At least she tries to be a science writer.
The best book on this subject that I have read recently is Spillover by David Quammen.
The H5N1 blog is a useful collection of ongoing information on the outbreak (he started reporting on it back at the start). Greg Laden also has some information.
From what I can see, one major problem is the number of health workers who have fallen ill and died and others who have fled for fear which leaves fewer to handle the situation; these include some senior doctors (dying not fleeing). It is only when the American doctors/nurses fall ill that it tends to hit our newspapers but the local doctors/nurses have been dying which will have long term consequences.
Here’s a health map with lots of up to date spreading info:
http://healthmap.org/promed/
Published Date: 2014-07-28 16:26:53
Subject: PRO/EAFR> Ebola virus disease – West Africa (20): WHO update
Archive Number: 20140728.425547
EBOLA VIRUS DISEASE – WEST AFRICA (20): WHO UPDATE
**************************************************
A ProMED-mail post
http://www.promedmail.org
ProMED-mail is a program of the
International Society for Infectious Diseases
http://www.isid.org
Date: Fri 25 Jul 2014
Source: WHO Regional Office for Africa, Epidemic and Pandemic Alert and
Response (EPR) Disease Outbreak News [edited]
http://www.afro.who.int/en/clusters-a-programmes/dpc/epidemic-a-pandemic-alert-and-response/outbreak-news/4233-ebola-virus-disease-west-africa-25-july-2014.html
http://promedmail.org/direct.php?id=20140728.425547 <====== LINK
@Crip Dyke #31 – What did I get wrong?
@Gregory in Seattle:
I don’t know that you got anything wrong. I’m really no expert here. I’m just go ogling and trying to read up.
But my post in #31 was in response not to any mistake, but to your question near the end of your post immediately before that. To wit:
I just tried to track down a source that looked credible and answer the question you raised. You know way more about this stuff than I do, so I thought you’d have done it yourself if you had time.
i was just trying to help out, I didn’t mean to imply anything was wrong.
@Crip Dyke #44 – Ah, my apologies. I was tired last night and read your comment as “Let’s find out from someone who isn’t pretending to know.” Just wanted to make sure I had my info correct.
When I read that the death rate was about 50%, I thought to myself “that’s not unlike the black death in the 14th century”. Makes you think what can happen if this virus starts spreading in say, Lagos. The slums there are not unlike medieval European cities, crowded, dirty and full of superstitious people.
It’s already there, from a plane passenger from Liberia.
I know that this question comes from watching too many bad movies, but considering the unprecedented size of this outbreak is it possible that ebolavirus could make the jump to being airborne transmissible? I know nothing of virology, particularly concerning hemorrhagic fevers, outside of what I could gather from Wiki, etc. on which I’ve found nothing to sate my curiosity. How could it even happen?
Just a link to something I may have missed would be appreciated, if at all possible.
http://www.twiv.tv/virology-101/
Thank you! At least from that (marking, of course, my failure at google-fu) I may be able to work towards an answer. My lexis-nexis and pubmed pass through logins are on the fritz at the moment. Thanks again.