Vaccines Alone Won’t Beat Ebola

A deep understanding of the Congo’s culture and time-honored public-health tactics are the keys to controlling the outbreak.

A person wearing blue gloves administers a vaccine to a man wearing a white shirt
Kenny-Katombe Butunka / Reuters

Updated on May 25 at 3:12 p.m. ET

Three people who had been infected with Ebola recently left an isolation ward at Wangata Hospital against medical advice, according to the Democratic Republic of the Congo’s Ministry of Health. The hospital lies in Mbandaka, a city of 1.2 million, where health workers are trying to contain the Congo’s ninth Ebola outbreak. One patient was on the mend, but decided to leave on Sunday and didn’t come back. Two more left with their families on Monday and went to church. One died at home, before his body was returned to the hospital for safe burial. The other returned voluntarily, before passing away at the hospital.

Choices like these make it harder to control this outbreak, which had already spread to 58 possible cases, as of Wednesday evening. But they are also understandable.

On a recent trip to the Congo, I met several survivors of past Ebola outbreaks, several of whom had left hospitals and gone home. Partly, that’s because an isolation ward can be a horrendous place, with walls and floors sometimes covered with vomit, feces, and urine. But partly, it’s also because the very concept of an isolation ward is an anathema to many Congolese people.

In the Congo, if you’re sick, you’re usually surrounded. Medical services are thin, so family members shoulder the burden of nursing their loved ones back to health. At one hospital I visited (well before the current outbreak), a family had camped outside a treatment building, waiting for their relatives inside to recuperate. Their laundry was drying on a washing line. “In an outbreak, you want to separate sick and healthy people, but here, if people are sick, everyone’s there,” one survivor told me. “Here, for we who live in communities, it is solitude that kills us.”

That mindset continues after death. Families will clean and dress the bodies of their loved ones. They’ll caress, kiss, and embrace them. Spouses might even spend a night next to their deceased partners. Through these bonds of affection, Ebola, which spreads through bodily fluids, can easily jump from one host into an entire family. The worst thing about the virus is not its deeply exaggerated bloodiness, but its ability to corrupt the bonds of community. It is a pathogen well suited to a world where sickness and death are met with touch and affection.

To bill these choices and practices, and others like them, as superstitions is misguided. These are the result of deeply held religious and cultural beliefs. “If you’re asking someone to not do the typical thing they do to grieve and mourn, you need to provide an appropriate alternative that achieves the same cultural end,” says Maimuna Majumder, an epidemiologist at MIT. “That’s usually the piece that goes missing. You can’t do that if you’re othering these kinds of practices.”

Fortunately, the Ministry of Health understands that.“We can’t forcibly prevent family members from touching a [patient],” says the spokesperson Jessica Ilunga. “So we’ve been really stepping up our community-engagement activities, by involving traditional and religious leaders. They have a huge influence on the community.”

That is how outbreaks are contained—without community buy-in, resources and fancy new technology won’t be enough. Unlike most of the Congo’s previous outbreaks, mobile laboratories are now operating, allowing researchers to confirm possible cases faster. As I reported on Monday, accurate digital maps are being made. Tablets with freely available software allow field workers to enter and compare data in real time without having to rely on printed paper. And most excitingly, health workers are starting to deploy an experimental vaccine called rVSV-ZEBOV.

The vaccine has been lauded as a “game changer”—and rightly so. In over 40 years of Ebola outbreaks, never has such a tool been available from the start. But it is still understudied in the field, and its existence doesn’t guarantee victory against the outbreak. A recent New York Times editorial, which somehow managed to describe a crisis whose case numbers are still growing as “contained,” also billed the vaccine’s use as “the first time Ebola was met with more than just the crude tools of quarantine and hospice care.”

“Of course you want vaccines, but yellow fever and cholera are perfect examples of disease where we have vaccines and still get raging outbreaks,” says Nahid Bhadelia, a physician at Boston University who helped to tackle Ebola in Sierra Leone. “We still need the public-health pillars.”

By that she means: finding infected people and tracking their contacts; ensuring hygienic practices that keep infections from spreading; and engaging with communities. These are old-school measures. Public Health 101. But they’re also the bedrock of any outbreak response. They’re vital for diseases that have no available vaccines or treatments, like Lassa fever, which is currently breaking out in Liberia, or Nipah, which has risen again in India. And they’re still vital when vaccines are available.

Around 7,500 doses of vaccine have so far been sent to the Congo, and 73 have been used as of Thursday afternoon, according to Guillaume Ngoie Mwamba. He is leading the DRC’s vaccination program and, to show people that the vaccine is safe, was the first to get the shot.

The plan is to start by immunizing health workers, people who have come into contact with confirmed patients, and contacts of those contacts. This “ring vaccination” strategy entirely depends on basic public health. Without a full list of contacts, the rings will be broken and the Ebola will slip out. “If you don’t know the chain, who do you vaccinate?” says Seth Berkley of Gavi, a nonprofit that has supported the vaccination campaign. That’s why the vaccine has thus far only been used in Mbandaka. It has taken longer to flesh out the contact lists in rural Bikoro and Iboko, where most cases have occurred, although Mwamba expects vaccination to begin there on Saturday.

Even with complete lists, there’s a lot of work to do. The Ministry of Health noted yesterday that some people from Bikoro were refusing to cooperate with health workers. To address that, Raoul Kamanda, a communications director from the Ministry of Health, held a meeting with a Bikoro citizens’ association to draw up plans for better communicating with the community.

For a start, there’s a language barrier. The Congo has upward of 200 languages. In Bikoro, around 90 percent of people speak Lingala, the main local dialect; to reach the people who don’t, the ministry is also translating its messages into N’Tomba, which is spoken by 40 percent of the region.

This kind of outreach must precede the deployment of the rVSV-ZEBOV vaccine, which brings with it several complications. Berkley says that people in the affected province are used to vaccination campaigns where entire communities get shots for diseases like measles or tetanus. But there aren’t enough doses of the Ebola vaccine for that. The ring-vaccination strategy, where only certain people get immunized, is a trickier concept to convey.

Since the vaccine hasn’t yet been licensed, it is being rolled out as part of a clinical trial.* In a similar small trial in Guinea, rVSV-ZEBOV proved to be 100 percent effective at preventing Ebola infections, but only during the tail end of an outbreak. It’s unlikely to offer perfect protection in a more realistic setting, so it’s vital that vaccinated people don’t let their guard down. The vaccine also takes 10 days to provide full protection; it has only been 16 days since the new Congo outbreak was first declared.

“If you say to people that it’s 100 percent effective, and all contacts get vaccinated, some subset of them will develop Ebola because they’ve already been incubating the virus,” says Berkley. “We have to be careful to not lose confidence in the vaccine.”

These challenges are not insurmountable. Mwamba tells me that there was originally some resistance to the vaccine among people in Mbandaka but after speaking to the communications team, everyone who was approached agreed to get the shot.

Reassuringly, a team of experts from Guinea, who were all involved in the rVSV-ZEBOV vaccination trial from 2015, arrived in Mbandaka on Sunday. They are intimately familiar with Ebola, ring vaccination, and this particular vaccine. “They’ve very important,” says Mwanba. “They’re training the Congolese, and I think by the end of this outbreak, we’ll have enough capacity to fight new epidemics on our own when they come again.” So far, the vaccination team includes six of the Guineans, along with 18 Congolese health workers. More people from Mbandaka and Bikoro are also being recruited to enhance local knowledge.

This vaccine may well help beat Ebola. But even if it does, its success will have been predicated on “crude tools”—on tracing contacts, on speaking a shared language, on cultural understanding, on trust. “It’s not surprising that people often don’t see how important these measures are,” says Majumder. “In public health, when you do your job right, no one knows that you do it.”


* An earlier version of this story incorrectly suggested that the use of the vaccine as part of a clinical trial affected the nature of informed consent. We regret the error.

Ed Yong is a former staff writer at The Atlantic. He won the Pulitzer Prize for Explanatory Reporting for his coverage of the COVID-19 pandemic.