At time of recording, an ongoing Ebola outbreak in Uganda has sickened 64 people; 24 people have died. The outbreak was declared on September 20th in a rural community but has since spread to Kampala, the sprawling capital city.
In recent years, health officials in Africa have become very adept at responding to Ebola outbreaks, and have relied on a highly effective vaccine that was developed in the wake of the 2014 West Africa Ebola outbreak. However, there is no vaccine for the particular strain of Ebola circulating in Uganda today.
In this episode, we speak with John Johnson, vaccine and epidemic response advisor with Doctors Without Boarders France to talk about the origins of this outbreak and how it has spread, how healthcare workers are responding, and why there’s no vaccine for this particular strain of Ebola when other Ebola vaccines have proven to be so effective.
What is the State of the Current Ebola Outbreak in Uganda?
John Johnson [00:00:00] It’s technically a different species of Ebola, and there are no current licensed vaccines or therapeutics against this strain.
Mark L. Goldberg [00:02:41] I know that prior to our speaking right now, you just got off a call with your team in Uganda. What did they tell you about the situation on the ground right now?
John Johnson [00:02:52] So it’s really sort of a pivotal moment in the outbreak, I’d say. So far there’s been about five districts that have been affected in Uganda, and three of them have gone over a month without any new cases, and one of them, it’s been almost two weeks, about 12 days. You know, we were looking at this as maybe the beginning of the end of the outbreak. What we’re seeing now is that there are some new cases in one of the districts that had gone 11 days without any new cases. And at the same time, we’ve had a couple imported cases into Kampala. So that’s not local spread in Kampala, but people that have traveled to Kampala while they were sick and there’s about 55 or so close contacts in Kampala that are being followed up. And Kampala is a very big city; what could happen there is that there are no new cases, and that’s great news, or there could be cases notified, in which case you have a large city where there’s local Ebola transmission going on and that’s really a powder keg situation. It’s a tenuous moment, I’d say.
Why is there a new Ebola outbreak in Uganda?
Mark L. Goldberg [00:03:54] What do we know about how this outbreak started and how it has evolved since?
John Johnson [00:04:02] So the outbreak was declared on the 20th of September, meaning the first case was really identified on the 19th of September. But if you look back and try to understand, you know, where this outbreak started, we’ve done some investigations and we’ve seen that there was a cluster of suspicious deaths in the area going back into mid to late July, and that’s probably where the outbreak really started. It’s difficult to say we haven’t found the index case yet, but we know it’s probably been spreading at a low level for around two months. But if you look at the epidemic curve, it was probably very sporadic cases for the first two months there, and then what we see as the peak so far was really sort of late September where we’d have about 6 to 8 cases per day, and now we’re really running at maybe one, two or zero cases notified each day.
Is there local spread of Ebola in Uganda’s capital, Kampala?
Mark L. Goldberg [00:04:54] So earlier you mentioned that there are now three confirmed cases in Kampala, imported you said so no evidence of local spread yet. Kampala is obviously a very large and sprawling city. How concerned are you that there may indeed be local spread in Kampala right now?
John Johnson [00:05:17] The biggest concern is the setting, so, like you said, Kampala is a very large city. It’s got a huge population, also a very international population with lots of people that travel. So, if there are cases in Kampala, that’s the biggest concern. However, I think the things that are good, if we can say things that are good, is that the cases that came into Kampala did not have a huge number of contacts, at least that we know of in the city. And those contacts have all been identified and are being followed very closely, either as contacts listed as just having an epidemiological link or contacts that may have symptoms of Ebola, in which case all of them have been isolated very quickly. But the three people that did have Ebola that were brought to Kampala, they were very quickly isolated. One of them unfortunately died and the other one has been followed up in an isolation center.
Without a vaccine, how are healthcare workers responding to Uganda’s Ebola outbreak?
Mark L. Goldberg [00:06:07] So one very successful strategy for containing Ebola, which worked very well in the D.R. Congo, is ring vaccination. When an outbreak is detected, health workers will vaccinate contacts, and then contacts of contacts and outbreaks can stay under control with limited damage. But for this particular strain of Ebola, there is no vaccine, and later in the conversation, I want to discuss with you why that is. But for now, can you explain how without access to a vaccine, health workers are responding to these cases?
John Johnson [00:06:44] Well, I guess first, I would argue that we did have a vaccine in the North Kivu outbreak, and we did use ring vaccination. It’s very difficult to say what effect that had on the outbreak. We assume there was a reduction in the number of cases and a reduction in the length of the outbreak but at the same time, we were vaccinating very early on in the outbreak, and the outbreak lasted still two years.
What are the differences between the Zaire and Sudan Strain of Ebola?
Mark L. Goldberg [00:07:08] And you’re referring to the last large outbreak in D.R. Congo in the Kivu region?
John Johnson [00:07:16] Yeah, correct. The last big outbreak of Ebola Zaire that we had was August of 2018 till sometime in 2020.
Mark L. Goldberg [00:07:24] And Zaire is the name of the strain of Ebola for which there is a workable vaccine, however, the one spreading right now in Uganda is a different strain called the Sudan strain.
John Johnson [00:07:35] Correct. And the Sudan strain, like you said, it’s technically a different species of Ebola, and there are no current licensed vaccines or therapeutics against this strain. And to answer your question about how health care workers are responding: it’s really back to where we were ten years ago, where we had to really rely on hygiene and infection control, personal protective equipment. So, I think we’ve all seen the photos of Ebola responders wearing the Tyvek suits, as well as goggles and gloves and rubber boots. We still use those things in any outbreak. It’s normal, but we have to rely very heavily on protecting ourselves with this equipment because we can’t rely on countermeasures like vaccines or effective therapeutics at this point.
Is the Ugandan health system under strain or threat of strain with the current Ebola outbreak?
Mark L. Goldberg [00:08:17] So on the comparison to the previous outbreak in West Africa, the big one: we saw back then, ten years ago and around 2014 in the West Africa Ebola outbreak, that the health system of Liberia collapsed under pressure and there was just a lot of excess mortality for lack of access to health care, not related to Ebola, like maternal mortality rates surged. Understanding that Liberia’s health system nine years ago was much weaker than Uganda’s relatively stronger health system today, is there concern at all that the health system of Uganda can come under strain, particularly if cases in Kampala seem to spread?
John Johnson [00:09:04] Certainly. I mean, if you look at past Ebola outbreaks, the damage caused by Ebola is not necessarily just the damage caused to individuals that contract Ebola or who die from Ebola, but it’s also all the collateral damage that goes along with having an Ebola outbreak in your country. And like you said, we see excess mortality because people avoid going to health centers. We see excess mortality because people just don’t have access to care like they might have had before, and we also see that a lot of resources are diverted from the national health care system towards the Ebola response, and that causes a lot of socioeconomic damage as well as health damage. If you think about the fact that Uganda, like the rest of the world, is just coming through two years of having a COVID pandemic. Uganda was also affected — they also had problems related to COVID in their country, and that weakened the health system further. But also, like you said, Uganda’s got a relatively strong and well-developed health system, a very active minister of health, as well as experience dealing with filoviruses, so they have a history of responding to Sudan Virus in the past, as well as Zaire Ebola virus and Marburg, so it’s not something that’s completely new for them. But if this is a big outbreak, it definitely will cause challenges for the health system.
When might there be a vaccine for the Sudan strain of Ebola?
Mark L. Goldberg [00:10:20] So on this question of vaccines, my understanding is that there are a few potential vaccines in various stages of development. What are some of these vaccines? And how likely is it that any time in the near future these vaccines for the Sudan strain that is currently driving the outbreak in Uganda will actually make it to health workers to do ring vaccination any time soon?
John Johnson [00:10:51] So it’s a really good question. Back when there was the big outbreak in West Africa, it was, you know, an unprecedented outbreak in terms of the number of countries, the number of patients and also the length of time. And I think at that point, a lot of the Filovirus research was diverted to focus on Zaire Ebola virus, and they sort of stopped really researching as much Sudan virus and the other viruses in the Ebola family. Which is reasonable, it makes sense, Zaire has caused the greatest number of outbreaks and also has the highest mortality. But I think some of the other Ebola viruses were really forgotten and we don’t have much in the way of countermeasures in terms of vaccinations and therapeutics for Sudan virus today. However, there are a few different vaccines under development and a few different therapeutics that are under development, and it looks like there will be some clinical trials involving vaccines as well as therapeutics if this outbreak continues long enough. The two vaccines that have been mostly discussed with the W.H.O. and partners in consultation were two different viral vector vaccines, ones produced by the Seven Institute, and the other is produced by the University of Oxford, and both of them have gone through phase one trials. There’s evidence that they appear to be safe and appear to be effective, at least in non-human primates. But they’re still fairly early on in the research stages and using them in this outbreak would be helpful to know if they actually work in real life, of course. But that’s the only way we get evidence on vaccines in terms of efficacy, we have to trial them in the middle of an outbreak, otherwise we won’t ever know if they work.
Does the Ugandan government currently support a vaccine trial?
Mark L. Goldberg [00:12:29] And do you have buy in right now from the government of Uganda who presumably would have to approve like a trial?
John Johnson [00:12:36] What we’ve seen in previous outbreaks is the way it works is typically the W.H.O. will pull together partners and work with the government of the country having the outbreak. They’ll set up a clinical trial protocol and they’ll work with a principal investigator from that country. So, yeah, it would be someone from Uganda really leading the trial, even if it’s heavily supported by W.H.O. and partners.
Mark L. Goldberg [00:12:56] And is that process underway? And if so, do you have an estimated timetable of when trials might start?
John Johnson [00:13:03] I can only say what I’ve heard. The WHO was fairly optimistic in the early part of October that the trial could begin before the end of October. So, this was stated by their head of immunization, vaccines, and biologicals, and they suggested that they might be able to start the trial by the end of October. I’m not sure if we’re meeting that goal at this point. I haven’t heard any news recently, but I’ve been surprised before. I know the protocols been written and I know the vaccines are available.
Why is there no vaccine for the Sudan strain of Ebola?
Mark L. Goldberg [00:13:30] So one of the reasons you cited that a vaccine for this particular strain isn’t widely available, hasn’t been sort of proven and tested, is that much focus was on the other strain that has caused more damage thus far, the Zaire strain, compared to the Sudan strain, which is ongoing in Uganda right now. If there were funding and political will for that kind of research, would a vaccine be available already? I mean, is this a situation that could have been a both and as opposed to like an either or?
John Johnson [00:14:08] I think the million-dollar question is why it seems like the people most interested in vaccine research for Ebola virus, smallpox are really the Americans. It’s pretty much been spearheaded by BARDA, which makes sense, their interest is in different viruses that could be used as weapons of war. And so, most of the filovirus research that we see is often funded by the United States.
What is BARDA?
Mark L. Goldberg [00:14:32] And BARDA is an acronym for the Biological Advanced Research…
John Johnson [00:14:39] And Development Agency, I believe.
Mark L. Goldberg [00:14:41] Okay. But BARDA is a U.S. government agency tasked with developing countermeasures to bio risks.
John Johnson [00:14:49] Exactly. So that’s their mandate, and if you look at previous Ebola outbreaks, most of the time when we have an Ebola outbreak, we’re asking BARDA for doses of vaccine as well as doses of therapeutics. Until recently, that was the way we got our hands on these things to treat patients. And it was from the goodwill of United States people that we got those things until the stockpile of Ebola vaccines was established a couple of years ago by the International Coordinating Group. So, the International Coordinating Group is a group that stockpiles vaccines for diseases that are at high risk of epidemic but there may not be a lot of vaccines available at any given time. So, meningitis, cholera, Ebola, and yellow fever. So, I think the question is it’s great that the US does all this research, but where is the interest for different pharmaceutical companies? Because this is something that is a public health issue. If you look at what we’ve learned from Ebola, I think most of what we’ve been able to accomplish with COVID was based on Ebola research, really. Monoclonal antibodies were a drug that we really, really spearheaded with the Ebola outbreak in West Africa, as well as the recent outbreaks in D.R. Congo and those showed great promise. And the two therapeutics that we have that are licensed for Ebola Zaire, are both monoclonal antibodies. And the company Regeneron that makes one of them was the company that began producing monoclonal antibodies for COVID, and we see that’s just sort of a wonder drug for COVID, if given early. So, a lot of this research that’s pioneered in Ebola is able to be transferred towards other diseases and it seems like there would be interest for pharmaceutical companies to be more active in Ebola research because it helps them learn what to do for other types of emerging diseases and diseases that could cause pandemics. And the other question is the role of Gavi, the Vaccine Alliance, in market shaping as well as the role of CEPI. It was created in Davos in 2017, I believe, and it’s an acronym for the Coalition for Epidemic Preparedness Innovations, it’s a public-private partnership. And really their mandate is to ensure development of countermeasures to emerging diseases or diseases where we don’t have effective vaccines yet. So, they’re looking at things like Ebola, like Zaire. They were very active in working on vaccination development for COVID. That’s sort of their mandate and Sudan virus seems like it would fall right in line with something CEPI should be working on.
Mark L. Goldberg [00:17:19] We have all these agencies, all these international coalitions that have been built up since the major West Africa Ebola outbreak almost ten years ago, yet we still don’t have a workable vaccine for this particular strain of the Sudan virus, and I’m wondering if it’s just like a matter of funding and political will?
John Johnson [00:17:41] I mean, I think so. I know it’s expensive. I know vaccine research is extremely expensive, and, you know, at least before COVID times, it used to take years and years and years, something like ten years, from start to finish for one vaccine at the cost of several billion dollars. I’m sure that some of that has changed because what we’ve learned from COVID is we’re able to sort of condense that timeline, and I think we’re able to lower costs if we look at the way that clinical trials can be run these days. But I think there’s just always the question of economics and cost benefit for the people that are investing in this new vaccine if it’s going to make a profit or not.
Mark L. Goldberg [00:18:18] So, you know, I know Ebola has a 21-day incubation period. So, over the next three weeks, what trends or indicators will you be looking towards in Uganda to suggest to you how this outbreak is trending?
John Johnson [00:18:37] The main important factor is the number of cases per day. Thankfully, we’re still running zero or one cases per day for the moment. Over the next three weeks, if we see a change in that, that’s obviously a concern. The other scary thing that we need to pay attention to is geographic spread. We are limited to two districts at this point, Mubende and Kassanda, where we’ve been seeing cases, and the other three districts that were affected seem like maybe they’re no longer affected, or they’ll get through their window of risk. If we see more geographic spread, if we see new districts where Ebola cases are spreading, that’s really the biggest cause for concern as well as the number of cases per day.
What is most important in treating Ebola?
Mark L. Goldberg [00:19:16] Is there anything else you wanted to mention? A question I didn’t ask, any point you wanted to make?
John Johnson [00:19:20] I always say this whenever I talk about Ebola, but it’s very interesting to talk about the therapeutics that are in development or the vaccines that are in development but even if you look at the past responses for Ebola Zaire, they’re part of the response. And they’re just another tool that we use in the response. The main response really to an Ebola outbreak is working with the community and ensuring that those people that are contacts or that are symptomatic for Ebola receive follow up and treatment as fast as possible. And even with the very good monoclonal antibodies that we have, they have to be given early and the best chances to save someone’s life if they’re infected with Ebola is early treatment, even if it means treatment with just supportive care, which is all we have really to offer to patients with Sudan virus today. But even if it’s just supportive care, your risk of death is much, much lower if you arrive soon rather than after several days. In fact, every day you wait outside of the hospital, your risk of mortality goes up basically by 10%. So, if you arrive the first day or the second day, you have symptoms, you have a very good chance of survival. But if you wait a week, that’s when we see the high mortality in Ebola. So really the most important thing to focus on in these responses is community engagement, is working with people at the community level and making sure that people who are affected by Ebola, that do have symptoms of Ebola, feel confident that they can receive treatment in health centers and in hospitals and that we can actually offer them something to save their lives rather than just sending them to an isolation room to go and die.
Mark L. Goldberg [00:21:03] John, thank you so much for your time and for your work on this.
John Johnson [00:21:08] Nice talking with you. Thanks, Mark.
Mark L. Goldberg [00:21:17] Thank you for listening to Global Dispatches. Our show is produced by me, Mark Leon Goldberg, and edited and mixed by Levi Sharp.