via Finding God in a Dog I’ve decided that I need to start documenting the spread of Ebola Virus Disease (EVD) in West Africa on a month-to-month basis. This is a story that is (or should be) on everyone’s radar already. My concern is that even the news-aware aren’t really tuned in to the grim reality of EVD, or how it could dramatically change our lives in the next couple of years. This initial post is a snapshot of my thoughts right now.
First, let’s start with the really scary stuff: the reported number of infected and dead have both so far followed a geometric progression
, doubling about every 29 days. Put another way, if the progression continues unchecked, we can expect the number of cases to continue to double every 29 days, which is the same as increasing tenfold approximately every 95 days. The last World Health Organization (WHO) report puts the number of cases at 3069
as of August 28th; unless conditions improve, therefore, we can expect about 30,000 cases by 1 December 2014, 300,000 by 6 March 2015, three million by 9 June 2015, and so on. If this progression were to continue unchecked by artificial or natural controls, we would see billions
of cases in the first half of 2016.
These numbers are really scary, but the thing to keep in mind is that this is what happens if EVD spreads uncontrolled
. There are several factors, both natural and artificial, which should control the epidemic. Let’s look at these in turn.
WHO has put together a nine month, half billion dollar plan
to curb the spread of EVD. This plan focuses primarily on building a health care infrastructure in Liberia, where conditions are at their worst. This effort isn’t a sure thing. It requires a lot of personnel (12,000 locals and 750 international experts), and depends on outside funding from governments, NGOs and private donors. So far, the first world’s response has been anemic. The plan calls for bringing the spread of Ebola under control (meaning, that it’s no longer increasing exponentially) within two to three months, and then halting new infections altogether in six to nine months
. WHO claims that EVD could affect more than 20,000 people
before they can get it under control. We should keep in mind that these numbers are probably minima
. If WHO is succeeding, we should know by December.
There is no known vaccine for EVD. British company GlaxoSmithKline (GSK) has an experimental vaccine
which has proven successful in monkeys. They’re going to start safety trials next week
to see whether the vaccine is safe for humans, followed by a larger immune response trial to see whether the vaccine produces the desired immune response. Assuming the vaccine passes both trials, a larger test in West Africa, to see whether the vaccine really prevents Ebola, is possible in early 2015.
If this vaccine doesn’t work, there are others in the pipeline —- but those will take longer to prove.
So, yeah, this is a crap shoot, but the payoff could be huge. Once we have a vaccine, we can control the spread of EVD by vaccinating around the hot zone
(a practice known as “ring vaccination”). We can also vaccinate vulnerable populations (such as health care workers) or even the general population (which may be necessary if EVD continues its geographic spread).
Possible Treatment (ZMAPP)
Right now the only treatment for Ebola is palliative care
—- replacing lost fluids and electrolytes, treating secondary infections, controlling fever, maintaining proper blood pressure and oxygen, and so on. There’s an experimental
drug, ZMAPP, which has been shown to reverse and cure Ebola in monkeys
. A prototype of this drug has been used on humans
, but two patients died
, and while five other patients recovered fully, it’s not clear that the drug had any effect on their recovery. Human trials of this new iteration of ZMAPP are due to begin soon.
It bears repeating that we don’t have a cure yet. We were able to treat Ebola patients in the US, but our best guess is that they recovered thanks to world-class palliative care at a world-class medical center. Also, it bears mentioning that homeopathic treatments —- such as snake venom
—- are more likely to kill you than heal you.
Presently the disease moves as infected people move. Most people in West Africa are not very mobile, and are limited by the Sahara Desert to the north, mountains to the east, and an ocean to the west. That still leaves a triangle from St. Louis, Senegal, to Western Ethiopia, to Port Elizabeth, South Africa. There’s close to a billion people in that triangle, and EVD is certainly capable of spreading through that area in the next 18 months.
Of course, these factors don’t matter much in the modern world. EVD spread to Nigeria through one infected passenger on an airliner
. Airlines are taking steps to control the spread, including monitoring passengers for symptoms, but these are filters, not guarantees. The more people that come down with EVD in West Africa, the greater the likelihood that it will spread elsewhere.
What If We Fail?
So, those are the possible mitigating factors. Absent those factors, if EVD continues to spread at an exponential rate, the number of cases will increase tenfold every 95 days. By Summer of 2015, we’d have millions of cases. By Fall of 2015, tens of millions. By Winter of 2015, hundreds of millions. By Spring of 2016, billions. Finally, by Fall of 2016, EVD should run out of people to infect. Everyone is either dead or recovered.
I think this scenario is unlikely. I don’t think that it’s highly
unlikely, and that, quite honestly, scares me. I think the most likely scenario is what I call the Reasonable Worst Case Scenario (below).
The Reasonable Worst Case Scenario
So, let’s suppose WHO can’t contain the epidemic and we don’t find a vaccine in the next year or two. EVD spreads out of control in West Africa, and eventually millions are affected from Senegal to Somalia to South Africa. In reality, this outcome is not that much worse than what we see today with HIV. The bigger damage will be economic. The first world, out of sheer terror, will curtail activity in sub-Sahara Africa, and many states will be cut off altogether. Nigeria’s booming economy will come to a screeching halt; South Africa will at least see a depression. Oil prices will shoot back up with Nigerian oil production offline. We’ll see a shortage of raw minerals similar to what occurred before China’s economy slowed down. There will be occasional first-world and second-world outbreaks, but the likelihood is that we’ll contain them and move on, similar to Hanta virus outbreaks in the USA. The rich of course fare much better than the poor. Even in the first world, there is a dramatic difference in medical care between Emory University Hospital and your local Oregon Health Plan clinic. Many outbreaks will be contained with cordons sanitaire
or isolation centers. Vaccine testing and production would continue as demand would be very
The Absolute Worst Case Scenario
So what about the worst case scenario that everyone’s afraid of? Suppose EVD spreads out of control, globally, and eventually reaches everywhere in the world. By the Autumn of 2016, there have been seven billion cases with 50%-90% fatalities. What now?
Once you’re infected, it is believed that you’re then immune to that strain
, at least for a few years. It’s also thought that some people carry a gene that makes them completely immune to EVD
, but we haven’t tested this. Assuming either of these conditions are true, we’re not looking at an extinction-level event. Instead, we’re looking at a few very hard years followed by a period of trying to rebuild. One could look to the past, during the Black Death, for an historical example. Beyond that, the only thing that’s guaranteed is that the world will look very different.