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News The Exponential Spread of Ebola

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  1. Sep 3, 2014 #1
    Have any of you been tracking the rate of new Ebola infections? It seems that there is pretty clear exponential growth, and the virus is anything but contained. Is anyone else bothered by this? By looking at this just mathematically, some huge swath of people will become infected. At a certain point the shear number of infections could threaten to collapse the efforts to contain it. Maybe the outbreak is just too big to contain. Maybe the outbreak is too slow moving to cause a health care collapse. I'm no epidemiologist, but I'm guessing that this outbreak will continue for years into the future.
     
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  3. Sep 3, 2014 #2

    Borek

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    Is there any reliable data that can be followed? I was under impression we have no clear idea about what is going on in Africa - just isolated data from several points where the outbreak was observed (but neither fully controlled nor contained).
     
  4. Sep 6, 2014 #3
    Most of the data on the outbreak is coming from the World Health Organization. Currently there are an estimated 125 new cases per day. I have seen reports that stating that this is the "tip of the iceberg" and that many cases are probably going unreported. The full extent is not clear to me.
     
  5. Sep 6, 2014 #4

    Chronos

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    I'm quite sure the number of ebola cases in africa are under reported. Western civilization does not feel it poses a threat, so it gets scant attention.
     
  6. Sep 6, 2014 #5

    SteamKing

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    It's hard to tell what is going on for certain, since news doesn't travel very fast or reliably from west Africa to the rest of the world.

    It would be of greater concern if it is found that the virus has spread out of west Africa and into the large cities of Europe or the Americas, since the travel infrastructure is well developed and large numbers of people are constantly on the move between cities and countries. Fortunately, this has not occurred yet.

    Right now, the virus outbreak is confined to west Africa, where travel and communication between villages is relatively slow. If the virus were to spread to Nigeria, for example, the large cities there could provide for thousands, if not millions, of potential victims.

    Unless the ebola virus mutates into some other milder strain than is currently existing, I don't think the outbreak will be long lasting: the current strain is very virulent and is fatal to a rather large percentage of those infected. When the number of hosts is depleted, if not eradicated entirely, the virus dies along with its victims.

    In the worst case scenario, if a village becomes infected with ebola, and all the villagers succumb, the spread of the virus is stopped at that point. If villagers who have potentially been infected travel to a village where no infection is present, then the virus spreads. The key to stop the spread is to make sure no large population center like a city becomes host to refugees from the countryside who may potentially be carrying the virus. In the absence of effective anti-viral treatment or a vaccine, quarantine is the best defense we have to contain the spread of the virus.

    The American volunteer doctors who were infected and survived ebola reportedly have developed anti-bodies to the virus. It might be possible to harvest these anti-bodies and develop a vaccine, but such a solution, if it is possible at all, would seem to be years away.

    [Late Edit]

    It's also not clear, but for various reasons, certain groups in west Africa may have naturally acquired immunity to the ebola virus currently spreading there. Since the virus apparently infects some of the animal population without the same virulent effects which human patients exhibit, it is thought that the individuals with immunity acquired it by either eating infected animals or by eating fruit which may have been contaminated by these animals:

    http://www.nytimes.com/2014/09/06/health/ebola-immunity.html
     
    Last edited: Sep 6, 2014
  7. Sep 6, 2014 #6

    Astronuc

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    Ebola has jumped into Nigeria because a diplomat violated a quarantine and took himself to Port Harcourt, Nigeria.

    Mobility in Africa has increased over the years, and now apparently some infected people flee the area to new areas and infect others outside the various quarantined areas.

    http://www.npr.org/blogs/goatsandso...infected-a-doctor-as-ebola-spreads-in-nigeria
    And there is concern that some folks may travel to Europe or North America.
    http://www.npr.org/blogs/goatsandso...ases-likely-in-u-s-air-traffic-analysis-shows
     
  8. Sep 6, 2014 #7

    [/QUOTE]
    The antibody thing from survivors has been tried before in other outbreaks and zero success rate in curing the disease was noted.

    As for the people "immune" to Ebola, as said in the text
    sounds like jabbeywocky. Any volunteers lining up to find out if they are immune. I don't think so.
     
  9. Sep 6, 2014 #8
    I listen to a BBC podcast that sheds some real light on some of the statistics we here reported in the news:

    http://www.bbc.co.uk/podcasts/series/moreorless

    Scroll down a bit to "How Deadly is Ebola?" to get a good numerical take on this.

    Probability-wise, consider the following:

    The probability that someone in Africa is infected with Ebola
    The probability that person is not showing symptoms (If they are showing symptons, it is not likely they will travel)
    The probability that person will then get on a plane

    Then:

    The probability that that person will infect another passenger (given that it is not an airborne disease).
    or
    THe probability they will arrive safely and infect another person here.

    All of the above has to happen for the disease to come here.

    -Dave K
     
  10. Sep 6, 2014 #9

    SteamKing

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    'Curing' a viral infection is one thing; using anti-bodies to develop a vaccine is different.

    Vaccines are administered to people who do not already have the infection, in order to stimulate their immune systems to produce anti-bodies to fight off a virus should an individual become exposed after vaccination.

    AFAIK, there are no cures for viral infections; the patient either recovers or he does not.
     
  11. Sep 6, 2014 #10

    lisab

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    I know you meant it as "probability a specific individual is infected", but as it's stated the probability of that statement being true is 100%.

    Given that the incubation period is about 3 weeks, and everyone who is sick goes through the incubation period, and they won't likely travel if sick*, this too is 100%.

    *in fact, people who are sick and travel anyway is believed to be how the disease spread to Lagos. A diplomat fled the quarantine area, went to a densely populated city, and sought treatment. He infected his doctor who continued to work after becoming sick, perhaps not realizing he had Ebola:

    http://abcnews.go.com/Health/diplomat-fled-quarantine-center-ebola-cluster-nigeria/story?id=25248411

    This one is less likely, but planes fly out of Africa full of passengers every day.

    I bet if you show up in any ER in North America with a fever and diarrhea, no one is going to suit up in full protective gear to treat you. They probably don't in most areas of Africa that aren't affected, either.

    Hmm. I don't feel much better, honestly!

    I mean, consider that diplomat in the link above. What if he/she had gone elsewhere -- Rio de Janeiro? Bangladesh? Miami? The fact is, it can (and already has) pop up elsewhere rather suddenly, because people travel easily.

    Where the outbreak goes is dependent on the comings and goings of the not-yet-sick people who have already been infected.
     
  12. Sep 7, 2014 #11
    Ok, fair

    Implicit in fact #2 though is that during the incubation period, people are not infectious. So no-one on the plane is at risk, was part of my point there. But remember, we're talking about the chances of someone in (West) Africa, who is infected, boarding a plane en-route to the U.S. Pretty low when you stack them.

    Per the person on the attached link (I wish there was a transcript) most hospitals are alerted to this fact and "containment would occur right away" for anyone that turned themselves in when feeling that sick. (And they would feel VERY sick.)

    What happened was already very improbable. But improbable things do occur.

    The chances of it spreading at a rate proportional to the current level of hysteria I think are still quite low. (Remember that SARS *was* airborne, and it was contained.)

    -Dave K
     
    Last edited: Sep 7, 2014
  13. Sep 7, 2014 #12
    There is another aspect to the issue: There is; ignorance, fear and distrust involved.


    http://www.pbs.org/newshour/rundown/raid-ebola-clinic-sparks-new-fears-infection-patients-flee/
     
  14. Sep 7, 2014 #13

    jim hardy

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    I guess it's just coincidence i recently stumbled across Jack London's 1910 short science-fiction story "Scarlet Plague" which describes a worldwide plague starting in 2013.

    Interesting read for his observations on society.

    http://www.gutenberg.org/ebooks/21970
     
  15. Sep 7, 2014 #14
  16. Sep 11, 2014 #15

    SteamKing

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  17. Sep 15, 2014 #16

    Astronuc

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    Fourth Sierra Leonean doctor dies from Ebola
    http://news.yahoo.com/fourth-sierra-leonean-doctor-dies-ebola-185820314.html

    Two doctors from the Netherlands have returned to NL for treatment.
     
  18. Sep 16, 2014 #17

    jim hardy

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  19. Sep 20, 2014 #18

    SixNein

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    The situation is pretty dire in Africa in my honest opinion. Even with the military support provided by Obama, it'll take several months for military support to go online.

    I am skeptical about one claim being tossed around in the media: the virus wouldn't be successful in America. I think people are underestimating ignorance. In addition, some of our cities have a high population density.
     
  20. Sep 21, 2014 #19

    jim hardy

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    I share your concern.

    http://www.npr.org/blogs/goatsandso...ce-of-west-africa-has-fueled-the-ebola-crisis
    It's comforting though that the virus didn't go rampant in Lagos...
    https://www.internationalsos.com/ebola/index.cfm?content_id=418&language_id=ENG

    Nigeria must have done something right.
    https://www.premiumtimesng.com/news...-case-left-minister.html#sthash.Lm6YjL4b.dpbs
     
  21. Sep 27, 2014 #20

    Astronuc

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