It’s relatively easy to think of ways in which things could go wrong, especially when dealing with a deadly disease like Ebola. I’m not optimistic about the likely course of events in West Africa, as you might gather from previous posts. But in this post I want to make an honest effort to envision what success would look like, then work backwards to see how it might be possible to get there from here. What follows is fantasy, but with a serious purpose.
Victory Over Ebola!
It has been 42 days and there have been no new cases in any of the countries affected by the West African epidemic! The last patient has either recovered or, sadly, died. Temporary facilities have been disassembled or burned, and hospital buildings thoroughly disinfected. Everyone has been through a harrowing experience but generous aid and technical assistance from around the world should help the affected countries get back on their feet.
Animal reservoirs of Ebola still exist; it would be wonderful to extinguish the virus worldwide but it’s really hard to imagine that. Ongoing efforts will be needed to discourage contact with infected animals, such as bush meat and fruit that may have been partially eaten by infected bats. Vaccination may reduce the risk of future outbreaks, although it will be difficult to maintain universal immunity in still-poor countries, and a vaccine might not confer immunity against a new strain. So as long as Ebola exists in the wild there will continue to be occasional rural outbreaks. The world obviously must never again let Ebola get out of control!
The “Effective Reproduction Rate” (Re) [Discussed in The Ebola Chain Reaction] was held down below one, month after month. That is, each person who came down with Ebola infected on average less than one other susceptible person. This was true not only in the aggregate but also in each country and region and neighborhood. The number of patients being cared for peaked, then began a slow but consistent decline, as the number of new patients each day was fewer than the day before. American troops were drawn down, then withdrawn completely, as there was no more need for additional beds.
Winning the War
Gradually, Re was forced lower and lower, down below one and then well below. How was this accomplished? Some combination of these factors:
- There were enough Ebola isolation beds for everyone who came down with the disease, in all affected countries, and the public had so much confidence in the care in those facilities that just about everyone who came down with Ebola was admitted to one before other family members were infected. Treatment measures and drugs like ZMapp improved the survival rate somewhat; this reduced suffering and contributed to confidence but didn’t otherwise help bring the epidemic to a stop.
- An Ebola vaccine, though not available in sufficient quantities to immunize everyone, was strategically given to American soldiers, healthcare providers and others who were likely to be exposed. Except for President Ellen Johnson Sirleaf and her husband the vaccine was not given out based on money or position.
- Infection of healthcare providers was almost completely stopped by:
- Universal availability of infection control gear.
- Comprehensive training of staff at all healthcare facilities.
- Procedures to minimize exposure of unprotected staff during admission or when an admitted patient begins showing Ebola symptoms.
- The Ebola vaccine, when it became available.
- Traditional funeral and burial practices were suspended by general consent after a massive public information campaign.
- People stopped breaking quarantine and/or lying about their Ebola exposure [Discussed in my first post], due to a broad consensus supported by religious and other opinion leaders.
- Urban modes of transmission turned out not to be significant, or were greatly reduced by changes in behaviors and other measures.
It would be great if one could imagine the final stage taking place before a vaccine is available, since that won’t be until around the end of the year at the earliest. Please comment if you think I’m too pessimistic, but I just don’t see how you get Re down below one in Liberia and Sierra Leone without a vaccine. Guinea is different, since their problem in recent weeks has been rural flare-ups due to infected citizens returning there from the other two countries. If Guinea can keep snuffing out these outbreaks — using the classic techniques of isolation, contact-tracing and monitoring — it might be able to get its part of the epidemic under control before the vaccine arrives.
Boots on the Ground
President Obama announced his plan to send 3,000 U.S. troops to Monrovia on September 16, 2014. [CNN 9/16/14] The troops were outfitted and trained in record time and arrived in Monrovia on [wildly hopeful] October 16, 2014. At that time Monrovia needed [a wildly optimistic guess] 1,000 additional beds to accommodate all current Ebola sufferers. The troops set to work building facilities for 1,700 beds, which became ready for patients between [optimistically] November 1 and November 16. By then all the beds were needed, and new patients kept seeking treatment at an increasing rate since Re was still over one. The U.S. identified the problem early and built another 1,700 beds (and trained all necessary staff), also in record time. This time around they got ahead of the curve and Monrovia was finally able to offer isolated care to all Ebola sufferers.
This was the most difficult period of the epidemic, when cases were still growing exponentially, and civil order was progressively undermined. The arrival of Americans had a wonderful effect on the public mood, however. American know-how and money ensured the provision of reliable water, electricity, trash removal and in particular food supplies.While there were a few situations in which small mobs gathered around American installations it was never necessary for a U.S. serviceman to file a single shot, and nobody was injured.
Due to their excellent training and high discipline, only a handful of U.S. troops became infected with Ebola. Those who did fall ill were medevaced back to the U.S., where a combination of excellent care and their own fitness led to a much lower mortality rate than experienced in Africa. Political blow-back from these Ebola casualties was muted due to a national consensus that American needed to do whatever it could to help with the humanitarian crisis in Western Africa. Once the vaccine became available U.S. troops were protected against Ebola and this problem stopped.
Meanwhile, home care kits that had been sent to rural areas proved helpful in reducing Re somewhat, but the key to success in those areas was the addition of more beds, in this case provided and staffed by Médecins Sans Frontières.
The African Union played the same role in Sierra Leone as the U.S. did in Liberia, with the same happy effects. (This strains credulity. The U.S. may have to do the same thing in Sierra Leone itself, which will be exponentially harder the longer it is delayed.)
Guinea continued to experience flare-ups due to travelers from Liberia and Sierra Leone, but it was able to snuff each of them out, and prevent the disease from getting established in its cities.
And They Lived Happily Ever After
Is this a fairy tale or can it happen? There are a lot of ways in which it could fail. To mention just a few:
- Every day counts when you’re battling an exponentially-growing problem. Any delay in any part of the process risks the numbers growing beyond anyone’s ability to manage them. Liberia may already be beyond the point of no return, but we’ll never know if we don’t try.
- Sierra Leone is about as bad off as Liberia. Is someone else really going to step in there, or does the U.S. have to go there as well?
- Political support for the U.S. intervention is likely to be tepid at the outset and could turn sharply against the project after there are casualties. This could force an early withdrawal even if the program seems to be working.
- There could be a further breakdown of civic order that would make it impossible to get the situation under control.
- Mistrust and rumor, or arrogance and privilege, could sabotage the program.
The scenario certainly could fail, but it might just work. We must hope against hope that it will succeed.