Marburg virus – which has no approved vaccines or drugs – is notorious for its killing ability, with as many as nine patients out of 10 having died from the disease in past outbreaks.
So when Rwandan officials announced an outbreak in that country just more than a month ago, the news was received with dismay.
However, those same authorities recently delivered a far more optimistic statement, reports NPR News.
“We are at a case fatality rate of 22.7% – probably among the lowest ever recorded (for a Marburg outbreak),” said Dr Yvan Butera, the Rwandan Minister of State for Health at a press conference hosted by Africa Centres for Disease Control and Prevention last week.
Additionally, two of the Marburg patients, who experienced multiple organ failure and were put on life support, have now been extubated – had their breathing tubes successfully removed – and have recovered from the virus.
“We believe this is the first time patients with Marburg virus have been extubated in Africa,” said Tedros Adhanom Ghebreyesus, director-general of the WHO. “These patients would have died in previous outbreaks.”
The number of new cases in Rwanda has also dwindled dramatically, from several a day to just four reported in the past two weeks, bringing the total for this outbreak to 66 patients and 15 deaths.
“It’s not yet time to declare victory, but we think we are headed in a good direction,” said Butera.
Public health experts are already using words like “remarkable”, “unprecedented” and “very encouraging” to characterise the response.
How did Rwanda, a country of some 14m, achieve this success? And what can other countries learn from its response?
Doing the basics really well
Rwanda is known for the horrific 1994 genocide, one of the worst in modern times. Since then, the country has charted a different path. In 20 years, life expectancy increased by 20 years from 47.5 years old in 2000 to 67.5 years old in 2021, about double the gains seen across the continent.
And Rwanda has spent decades building up a robust healthcare system.
“The health infrastructure, the healthcare providers in Rwanda … they're really, really great,” said Dr Craig Spencer, an emergency physician and professor at Brown University School of Public Health.
Spencer specialises in global health issues and has been following the Rwandan outbreak closely.
There are well-run hospitals and well-trained nurses and doctors, he said. There are laboratories that can quickly do diagnostic testing. There is personal protective equipment for medical workers.
For this outbreak, there was the know-how and infrastructure to set up a separate Marburg treatment facility. That’s been a boon for other patients and medical staff, preventing exposure to the virus – which crosses over from bats to humans and can be transmitted through bodily fluids like blood, sweat and diarrhoea.
And even though there aren’t approved medications to treat Marburg, patients in Rwanda have received good supportive care for all their symptoms, like the IV fluids critical for high fevers, nausea, vomiting and diarrhoea.
This stands in stark contrast to the response in past Marburg scenarios. For example, the Democratic Republic of Congo – right next door to Rwanda – had an outbreak between 1998 and 2000.
Dr Daniel Bausch, now a professor at the London School of Hygiene and Tropical Medicine and an expert in tropical diseases like Marburg, provided care in that outbreak.
He said what that country’s health centres were able to offer patients was rudimentary at best.
“We called it a care centre or treatment centre, but really, it was a separate mud hut in which people were placed. We didn’t have anything available to us,” he remembers.
“Patients were lucky if they got paracetamol or Tylenol and some fluids to drink, if they could get them down without the nausea and vomiting preventing them.”
That outbreak had a fatality rate of 83% with 154 cases and 128 deaths.
In the world’s 18 recorded Marburg outbreaks, the mortality rate varies considerably. Several small outbreaks have had fatality rates below 30% but the largest outbreak, in Angola in 2004 and 2005, had a case fatality rate of 90% with 252 cases and 227 deaths.
Rwanda’s “more modern medical centres” make a big difference, Bausch said.
Getting to patients quickly
It isn’t just the calibre of care that makes a difference, but also the speed with which patients get care.
As soon as the outbreak started, Rwandan officials jump-started a major operation to trace the contacts of those who were infected, monitoring the health of more than 1 000 relatives, friends, healthcare workers and others at risk.
They also started door-to-door surveillance in neighbourhoods where there might have been an exposure.
And they did a lot of testing: more than 6 000 tests, especially among healthcare workers, who’ve comprised 80% of the Marburg patients in this outbreak.
Spencer said many of these capabilities were built up during the Covid pandemic and could be rolled out rapidly.
“In Rwanda, you have providers who are able – within hours of this outbreak being declared – to get tested,” said Spencer, who has worked with Doctors Without Borders treating Ebola patients.
“Rwanda’s testing is absolutely remarkable in terms of the response.”
This surveillance and testing allowed “us to detect cases quickly and provide them with treatments in the very, very early phases of their diseases”, Butera said, adding that caring for patients before they become critically ill helped lower the mortality rate.
Embracing experimental vaccines, drugs
Rwanda’s speed carried over into other anti-Marburg efforts.
“Everything I have witnessed was really expedited,” says the WHO’s Ghebreyesus, who visited Rwanda last week and said what he saw was “very encouraging”.
While there are no vaccines or treatments approved for Marburg, Rwanda acted quickly to get experimental vaccines and treatments to people at the centre of the outbreak.
“I can’t imagine another scenario in which a country went from identifying this outbreak to just more than a week later having investigational (experimental) vaccines already being provided to frontline healthcare workers,” said Spencer, adding that the doses started being administered the same day they arrived.
The non-profit Sabin Vaccine Institute provided the doses, which were developed with major support from the US Government.
“I rarely use the word unprecedented in global health response” Spencer said, but this speed was “unprecedented”.
The vaccine itself is still in development. Testing has shown that it’s safe – but not whether it actually works. Nonetheless, Rwanda decided to inoculate those at risk, hoping it would help.
Those officials also decided to vaccinate without a randomised controlled trial, where a segment of the recipients get a placebo.
Some in the international scientific community say this was a missed opportunity to start learning whether the vaccine is effective, although they concede that it’s far more complicated and slow to roll out a trial.
And the size of the outbreak was unlikely to yield enough data to be conclusive.
Did the vaccines help stop the spread or reduce the mortality rate? It’s impossible to know, said Bausch, noting that in the first recorded Marburg outbreak – in 1967 in Marburg, Germany and in what was then Yugoslavia – the mortality rate was 23% with only good supportive care.
Meanwhile, in Rwanda, the next round of vaccines will go to at-risk groups, including mine workers who are in close proximity to the fruit bats that can spread Marburg; that vaccine effort will be randomised.
In addition to the vaccines, Rwanda very swiftly started giving patients two medications, the antiviral called Remdesivir and a monoclonal antibody.
As with the vaccine, they hoped these treatments would help even though they haven’t been approved for Marburg.
In early stumble, a course correction
In addition to the speed and high-quality patient care, there’s another less glamorous, but equally important, dimension to quashing Marburg and other viruses, Bausch said.
It’s infection control: basically, ensuring Marburg patients don’t infect others. In the hospital, this means that staff take precautions like wearing gowns, masks and double gloves. In public, it can mean sanitising shared items like motorcycle helmets and installing hand-washing stations in public places, as Rwanda has done.
Rwanda stumbled early on with infection control. That’s because it took a couple of weeks to diagnose the disease in the person who is considered the first patient in this outbreak – and the first known Marburg case in the country.
That individual, who possibly contracted the virus from exposure to fruit bats in a mining cave, also had a severe case of malaria.
Clinicians did not determine that Marburg was also present until other people around that patient started falling ill.
As a result, many healthcare workers were exposed before infection control measures were improved.
Rwanda rapidly improved infection control once officials understood what they were dealing with – and not just in health facilities. The mining community linked to the initial patient has seen several cases.
So surveillance needs to be sure to cover those populations, said Rob Holden, WHO’s incident manager for Marburg.
“We fine-tune, we refine, we reinforce all of our surveillance systems, our contact follow-ups, our investigations, and we leave no stone unturned. If we let our guard down, then I think we'll end up with some nasty surprises and a very long tail on this outbreak.”
Spencer agreed.
But he is optimistic. He said Rwanda’s robust health infrastructure and speedy response has helped protect the rest of the world from a much bigger Marburg outbreak.
See more from MedicalBrief archives:
Marburg virus kills eight in Rwanda
Vaccine candidates offer hope for African Marburg spread
Marburg disease strikes Tanzania, kills five