The base graph is the WHO/CDC released figures on the Wikipedia page about the outbreak.
Posted on 09/15/2014 2:50:13 PM PDT by scouter
While this article isn’t the one I had recalled, it does talk a bit about pre-symptomatic contagiousness.
http://scienceblogs.com/gregladen/2014/07/27/ebola-outbreak-in-west-africa-some-basic-information/
I’ll keep looking.
Aha. The place that the pre-symptomatic contagiousness was noted has been removed from the website, but was originally found at
While that page no longer exists, it was, while it was up, cited by many other websites. If you google this phrase:
cdc-changes-criteria-for-ebola-transmission-admits-being-within-3-feet-or-in-same-room-can-cause-infection
which was basically the name of the page, you will find a host of reputable sites pointing to this page. So what happened? Was the original posting in error, and removed? Or was I removed for other (politically correct) reasons?
Very good question. Almost worthy of its own thread.
Your math is not making sense to me.
First a DTR (Daily Transmission Rate) of 1.004 is way too low.
And I’m not sure what you are doing putting both the DTR and the DaysOut in the exponent. That might work in your formula, but I don’t think the formula makes logical sense.
Work it through one day at a time and see if you get the same result.
Start with 100 cases and let’s do just 3 days.
If you have 100 cases on day 0 and the DTR is 1.004 then you would have 100*1.004 = 100.4 on day 1, and 100.4x 1.004 = 100.8 on day 2, and 101.2 on day 3.
But if you plug it into your formula for 3 days, then you get:
100^(((1.004-1)*3)+1=
100^(.004*3)+1 =
100^(.012+1) =
100^1.012 = 105.6, but it should equal the same result that we walked through day by day. So either your formula is wrong, or I don’t understand exactly what you are doing.
http://www.cdc.gov/vhf/ebola/transmission/index.html
http://www.cdc.gov/vhf/ebola/hcp/clinician-information-us-healthcare-settings.html
http://www.cdc.gov/vhf/ebola/hcp/infection-prevention-and-control-recommendations.html
If it were to spread in the U.S.A., it would likely be carried to all points in the country quickly by travelers then stay in the communities for several years. Unlike flus, it’s an extremely tough virus that lives a long time on dry surfaces in a great range of temperatures, leaves survivors contagious for about six months and spreads very slowly but surely. Generally, nearly all people would be resigned to trying to live as they have.
‘Don’t Touch the Walls’: Ebola Fears Infect an African Hospital
http://www.freerepublic.com/focus/f-news/3190930/posts
Patrick Sawyer became infected in Liberia, traveled to Nigeria, denied to medical folks that he had it and urinated on nurses in defiance. Medical personnel contracted the disease from him. So he used a weapon that was more dangerous than firearms.
The disease is transferable to dogs that might then infect their owners.
Ebola Virus: From Wildlife To Dogs
ScienceDaily
http://www.sciencedaily.com/releases/2005/06/050608065550.htm
Date:
June 9, 2005
Source:
Institut De Recherche Pour Le Développement
“Ebola virus antibodies were detected in dogs exposed to the virus during the latest epidemics, which suggests that these animals may well have been infected and can therefore be a new source of transmission to humans.”
How is Ebola spread?
The virus is spread through direct contact (through broken skin or mucous membranes) with blood and body fluids (urine, feces, saliva, vomit, and semen) of a person who is sick with Ebola, or with objects (like needles) that have been contaminated with the virus. Ebola is not spread through the air or by water or, in general, by food; however, in Africa, Ebola may be spread as a result of handling bushmeat (wild animals hunted for food) and contact with infected bats.
Can I get Ebola from a person who is infected but doesn’t have fever or any symptoms?
No. A person infected with Ebola is not contagious until symptoms appear.
http://www.cdc.gov/vhf/ebola/outbreaks/guinea/qa.html
We’ve seen many articles with headlines about cures (as with the false reports about AIDS cures for decades), but there’s no cure and no vaccine. Blood serums might help as a treatment (not known), but most of those who recover will be very messed up—mind and body—for the remainder of their short lives.
Given your qualifications for creating these projections, as to the qualifiers effecting the data as it unfolds in the real world, in your work with statistics are their not certain logarithmic formulae that can be applied, particularly with the data when the available pool becomes larger and perhaps more accurate, that might tighten your projections around probabilities?
Wouldn't it be more accurate to hash out columns rated against their range of probabilities, e.g., 10-20 % 10 to 20 millions; 20-30 % 10 to 5 millions, etc?
Thanks for the ping!
Ebola is transmitted exclusively by bodily fluids and not by air, like colds and the flu. In developed countries, Ebola would be less transmissible because of less crowding, much greater sanitation as a matter of routine, and the availability of modern medical care. Finally, in the developed countries, isolation measures would prevent the hospitals from being centers of Ebola infection as they commonly are in Africa.
Sir,
I have an advanced degree in mathematics, and unfortunately I confirmed your findings last week when the death total was near 1500. When the WHO reported that the number of cases was doubling every three weeks, I quickly realized that there would be over a billion people with Ebola in 12 months unless something changes. Therefore, I concur with your projection. We are facing an apocalyptic scenario unless something fundamentally changes. May God help us.
Thanks,
M.F.
I Googled that phrase, and all that comes up are a bunch of conspiracy sites (which really don’t interest me). I did go to one, and it had a screenshot from the CDC, which supposedly showed something that the CDC later “hid” by removing that particular page. Since that one site had screenshotted the CDC web page, I looked at it and compared to what is currently posted on the CDC. The page was edited and rearranged, but the information there is identical.
Despite the supposed conspiracy and “admission” that Ebola is suspected to transmit through droplets—which has been suspected for decades, and so hardly is a new “admission”—I do not see anything on any page that contradicts anything I know about Ebola.
Every single medical journal article I have read says that Ebola is only transmissible when symptoms appear, and that it becomes more transmissible as symptoms worsen. It can remain infectious in certain compartmentalized fluids for weeks after infection, but will eventually clear.
Quite true. In Africa, theft and corruption undermine virtually every hospital and medical clinic. Travelers who venture outside of major African cities are sometimes urged to bring along emergency medical kits since antibiotics, bandages, and hypodermic needles are often unavailable or local examples are unsafe to use.
The base graph is the WHO/CDC released figures on the Wikipedia page about the outbreak.
Ebola would spread even faster in developed countries.
* Travel, eating out, shopping, public entertainment, etc., are much more common.
* Customers are forbidden from wearing masks in many public places.
* There’s a popular aversion to hand-washing, where even medical professionals are hastily using hand sanitizer instead of scrubbing.
* Although the floors are shiny, many hospitals and clinics even smell filthy compared to such places forty years ago.
* There’s also the trend toward socio-political spite between groups (balkanization).
* The aversion to hygiene is most apparent in public places around tourist centers in western states.
* Our country has far too few medical employees and hospital beds relative to the population.
* There will not be enough quarantine facilities for more than a very few.
* The economy would completely seize, so fearful market interests (sponsors, most influential political constituents,...) are motivated to prevent any measures that could alarm the population and decrease revenues. They would lose all that they have during an epidemic and will take all that they can get in advance.
* Drug abuse is very common and has been legitimized in some states by legalization.
* The few highest bidders for questionable treatments in very short supply would do anything to get them, exacerbating the situation.
Every body fluid you can think of. Sweat. Spit. Urine. Feces. All of these exit the bodies of the victims in copious amounts and all of these have copious amounts of the virus. Cough or spray aerosols the virus over a relatively large area. Being in a car with someone who is sick has already spread the disease and killed others.
In developed countries, Ebola would be less transmissible because of less crowding, much greater sanitation as a matter of routine, and the availability of modern medical care.
You would think. Except for subways, Walmarts, restaurants, malls, trains, airplanes, schools, immigrants living stacked on one another to save money, etc. etc. If anything it's just as crowded in most of our major cities as it is in Africa.
Finally, in the developed countries, isolation measures would prevent the hospitals from being centers of Ebola infection as they commonly are in Africa.
People routinely get "hospital" diseases such as mrsa. That can't even be eradicated. Unless ALL medical personnel are willing to suit up every time they see a patient with the sniffles, runny nose, fever or diarrhea this disease will spread just as surely as it is in Africa.
We have a better health care system, and are able to keep patients quarantined while tests are run to determine if they do have Ebola (if they have the travel history to suggest such testing is worthwhile). In the hospital, we practice good infection control measures.
An even more important factor is that we do not have the customs that they have in Africa.
That's right. The USA has 128 Million people who commute to work every day. Only 75% of these people drive alone. The rest really "commute", sharing the ride by carpooling, bus, train, subway, plane. Lots of filthy people contact all along the way.
Most of those people interact with others a couple of times each day at fast food joints, convenience stores, gas stations, dry cleaners, grocery stores, big box stores, etc., exchanging money, credit cards, products, etc., hand to hand.
Probably half of these working people have at least one meeting each day, crammed into little meeting rooms.
There are also 200 Million people who don't go to work, but interact with other people daily at schools, daycares, stores, bars, on the street, sporting events, etc.
People in the USA are just as filthy and stupid as people in the worst cultural conditions in Africa, just in different ways.
When ebola starts spreading in the USA, it will travel faster and farther than in Africa. Aiding in its spread will be the people saying, "there's nothing to worry about here," to their last gurgling gasp.
In the US and other developed countries, there are well-established public health measures to identify, isolate, and treat dangerous infectious disease cases and contacts. This would probably suffice for even Ebola, but, if not, the menace of a general outbreak would swiftly lead to stronger measures such as the cancellation of public events and suspension of non-essential work, shopping, and travel.
An outbreak of Ebola in a developed country would lead to face masks, gloves, and the general spraying of disinfectant becoming routine in public places. In contrast, in Africa, poverty, corruption, theft, and the shambolic nature of its societies commonly make it impossible for even medical personnel who treat Ebola to have the benefit of containment garments and disinfectants.
In a developed country that suffered an Ebola outbreak, medical care for the disease would improve rapidly, with new treatments and vaccines fast tracked into use. The result would almost certainly be the rapid and permanent containment of any such Ebola outbreak, just as bird flu and SARS were contained despite the dire predictions that attached to them.
In sum, Ebola is cause for concern and excitement in the US and other developed countries but is extremely unlikely to generate more than a relatively small number of cases.
There are many ways in which our culture is not conducive to the spread of a disease like Ebola.
The most important way is in the way we treat the dead. We don't wash the bodies, we don't give them enemas. Instead, we ship them off to a mortuary to prepare for burial or cremation. During the funeral, most people do not touch the body. This is very different than the African burial customs which are completely responsible for the early spread of Ebola. Later on, nocosomial infection became important.
For another thing, even in the most crowded situations, we avoid touching each other. I noticed this at Disneyworld over the summer: no matter how crowded an area was, every American had a no-touch zone around him or herself. This was not true of some of the foreigners, who did not seem to mind bumping or being bumped.
Ebola requires direct contact to spread. While other potential means of spread have been mentioned--droplet transmission, fomites--there is no real evidence supporting those means. People who are sick enough with Ebola to be shedding virus in fluids aren't going to be out riding buses and so forth--they are really, really sick. I could see such a person hunkering down in their home until they die, but not being out and about contaminating public restrooms with their diarrhea and vomit.
If Ebola were easy to catch, this thing would have already gone around the world. Compare to influenza--it is about to sweep the northern hemisphere again, and it will essentially hit every continent at once, because it spreads easily and it spreads through aerosols. Ebola, on the other hand, is still confined to three countries--the imported outbreak in Nigeria is controlled, and I don't think there are new cases.
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