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The answer is: it depends.

I haven’t seen any updated mortality figures in about five days. I anticipate the death toll to be at 1300 soon. If it is already 1300, then the death rate is doubling every four to six days now. This will accelerate if it is truly out of control. The curve was already exponential, but if the trend continues and the death rate starts doubling every couple of days then you have a real problem.

Nobody has talked about the R0 factor yet. This is also called ‘R naught’. R naught is the ‘basic reproductive number’, and used in epidemiology to figure out what level of response you need to start lining up in order to deal with what you are up against. It is a variable used in a complex differential equation called a Jacobian, that is used to model this sort of stuff.

And you thought you’d never use Calculus!

An R0 < 1 meant that an infection (like, and especially like, Ebola Zaire) would burn out in the ‘long run’. An R0 > 1 means that the likelihood of the infection spreading through a population is probable. The higher the R naught, the higher the probability, and the faster the infection rate. R naught is NOT a probability, it’s a ratio related to number of cases and number of deaths.

For diseases that don’t include a ‘intermediate vector’, which would be a mosquito (for malaria, for example), the R naught is not as useful an indicator of how fast a disease will spread, nor can it be used to determine how many healthy people in a given uninfected population need to be vaccinated in order to stop the spread of the disease.

If there are no intermediate vectors, then the proportion of uninfected people you need to vaccinate to stop the contagion is roughly equal to (1-1/R0).

It would be logical that somebody has tried to nail down the R naught at this point. That will allow you to run a projection, which would look like a curve plotted with time on the X axis and cases on the Y.

You take that plot, you print it out, and then you start gathering your reports, and you plot your numbers over a period of a few days. If your points line up with the curve, you’ve confirmed your R0.

If there’s an intermediary vector, then R0 is going to be a bigger number depending on what species is propagating the pathogen. If the intermediary vector is the primary vector of the disease, your R0 will be lower. If the intermediary is only a secondary vector, meaning both humans and the species in question can spread the bug, then you have to worry about what the intermediary is.

If it is a common mosquito, you should worry a lot. If it is a rare mosquito, or something that crawls or doesn’t reproduce efficiently, then you have less to worry about.

So, to take your question, and replace it with the exact right, no bullshyte question a knowledgeable reporter might ask, the right question to ask is:

“Doctor, what is the R0 of Ebola Guinea, and if you haven’t established R0 yet, what is the current estimate being used in the models you are using for policy making purposes at this point?”

Any value of R0 higher than 1 is bad news. The higher R0 is, the closer the scenarios get to a ‘Contagion’ scenario. A value of 2 or higher and it will mean a change in our way of living until a vaccine is identified.

The good news here is that there’s some sort of serum being used. Interestingly, the method of testing isn’t unlike what would happen in the movie.

This is why I asked the question I did in the last post. Can you infect a monkey with it, and will they develop the same symptoms. If you can’t, then you have to test it on human beings, because you don’t have any other choice.

Maybe they did, and maybe they didn’t. You can use rats, but rats aren’t as close genetically as chimps are. In the end, there is very, very little to lose in human testing on something like this, outside of mutation.

The worst case scenario is that Guinea mutates into something like Reston, but lethal to people. Nothing says a pathogen like this can’t take that kind of turn. What is MORE LIKELY to happen if there is a mutation, is that the mutation may change the properties of the disease such that it may no longer kill people.

That’s the nature of mutations - it is worse than roulette. You get a bug that can do this, its like hitting Satan’s jackpot - everybody loses - but the chances of Satan pulling the lever and getting all million wheels to come up ‘6’s’ again and give you an even more lethal version the Spanish Flu, for example, is incredibly remote.

It’s more likely a mutation screws up the virus’ ability to do damage than it is increase its ability to do so.

I met a historian once out of UC Davis who provided me with compelling evidence that the what killed people in Europe in the 1500’s was actually a strain of Ebola, and not a flu. People died quick, hemorrhaged a lot, and it killed a lot of people, but eventually burned itself out.

He went back to the diaries of the medical folks of the day and correlated the symptoms. Sure sounded more like Ebola than something else.

R naught is the right question to ask at this point. Whatever R naught FEMA and the UN is using will tell you everything you need to know.