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To: ansel12

There were, and always are, caveats with an infectious disease.

Epidemiology is math - differential equations. These equations essentially factor in the speeds of things.

If you have a tank filling with water, and the tank has an outpipe that is smaller than the inpipe, then the tank will still fill, but more slowly. That’s a simplified sort of model.

In Sep, three things were true:

1. The test for Ebola was not very good (still true)
2. There is no vaccine (still true enough - there are vaccines under development)
3. There are no serums or drugs effective against the disease (evidence suggests this may no longer be true. What is very true is that these drugs are not being used on a wide spread basis).

In Liberia, a doctor was successful treating Ebola Guinea with Lamivudine. There are others that ARE NOT ZMapp (when’s the last time you heard the word ZMapp) that have similar methods of action to Lamivudine that may be effective.

Black Agnes has a pretty good bead on the pharmaceutical angle.

The basic model breaks down in terms of three groups - Susceptible, Infectious, and Recovered

However, the model also has variables that impact it - like ‘Interventions’ and ‘Mortality’.

Interventions would be the use of quarantines, etc.

Mortality is, obviously, the dead. Eventually you run out of people to infect.

A big deal variable in this is called R nought, or R0, or the secondary infection rate. With this disease it only takes as little as 10 viruses in a droplet to infect a person. On top of that, we don’t really know when people start shedding the virus.

As long as R0 is bigger than 1, then the disease will continue to grow. Interventions drive the R0 less than 1, which means the disease will begin to burn itself out.

The current R0, globally, is about 2 - maybe higher given that the WHO is actively conditioning their figures (by a factor of 3).

AIDS drugs are being looked at as possible effective interventions. As for a vaccine, the REAL question is WHEN you can deploy it. For a vaccine to be effective in stopping a disease, you have to vaccinate enough people to choke out the number of Susceptible Class people from the path of the contagion. You can calculate the percent using R0:

1 - 1/R0, stated in percent, is the proportion of the population you need to vaccinate for the vaccine to stop the disease. If R0 = 2, then 1 - 1/2 = 50% need to be vaccinated.

That’s a lot of vaccine.

So, the long answer is:

1. If there is no vaccine by June 2015 - Yes.
2. If there is no effective drug intervention (AIDS drugs perhaps) - Yes.

Quarantines CAN WORK, and have worked throughout history. If we don’t quarantine, then again, Yes.

The disease will reach a tipping point - the disease popping up in too many places spreading too rapidly to contain without either a drug or a vaccine, and too fast to contain with a quarantine.

Or, we will come up with effective interventions. All my post did was indicate the mathematical pattern.


22 posted on 10/30/2014 11:19:33 AM PDT by RinaseaofDs
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To: RinaseaofDs

So do you still think a billion will be infected by 2016?


23 posted on 10/30/2014 11:33:44 AM PDT by ansel12
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To: RinaseaofDs
The disease will reach a tipping point - the disease popping up in too many places spreading too rapidly to contain without either a drug or a vaccine, and too fast to contain with a quarantine.

They tested that theory in West Point, but it turns out people avoided touching the dying and dead and the disease was kept in check using home-made disease control and ambulance services: http://online.wsj.com/articles/liberian-slum-takes-ebola-treatment-into-its-own-hands-1414080932

The disease simply cannot double each month without keeping the dying at home, washing the dead, etc. Even a modest effort like in West Point is enough to avoid your scenario and non-third-world countries have zero chance of your scenario.

31 posted on 10/31/2014 3:54:51 AM PDT by palmer (Thank you for your patience.)
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