Congolese health officials arrange the first batch of experimental Ebola vaccines in Kinshasa. Kenny-Katombe Butunka / Reuters

Updated on May 17 at 3:54 p.m. ET

The current Ebola outbreak in the Democratic Republic of Congo has thus far been confined to remote rural areas, but one case has now been confirmed in Mbandaka, a city of almost 1.2 million people. “We are moving to a new phase of the epidemic, and we are putting all the means in place to respond to it in a quick and effective way,” said Oly Ilunga, the DRC’s minister of health, on Wednesday evening.

The outbreak initially hit the northwestern town of Bikoro and a nearby village called Ikoko-Impenge that is 30 kilometers away. Both are small and hard to reach, especially in the current rainy season, when roads become pockmarked with gullies and potholes. Mbandaka’s larger population, and its location on the Congo River, provides new opportunities for the virus to spread. And, at around 150 kilometers from Bikoro, it significantly widens the area affected by the outbreak. “Confirmation of urban Ebola in DRC is a game changer,” Peter Salama, from the World Health Organization, tweeted. “The challenge just got much, much tougher.”  

“It’s a big city,” says Patrick Mukadi, a lab director at the National Institute for Biomedical Research, or INRB,  in Kinshasa. “There’s a lot of people passing through, and doing business with surrounding countries. There are regular flights between Mbandaka and Kinshasa [the capital city with a population of more than 11 million]. There are boats to Kinshasa, although it takes two weeks. We don’t know if the outbreak will be big, but it’s better to overestimate than underestimate in terms of the response.”

The outbreak only spread to a city after a rural origin—and that could make a huge difference. “Having that advanced warning meant that a lot of things were already put in place,” says Nicole Hoff from UCLA, who is currently in the Congo. “All the emergency operations that were being set up were in Mbandaka, since it’s the closest city to Bikoro. We’ve always discussed what would happen if Ebola made it to the city.”  

The new case was confirmed in Wangata, one of three “health zones” in Mbandaka, and the closest to Bikoro. The newly confirmed patient was at a funeral in Bikoro before traveling to Mbandaka and attending a church service, according to Jessica Ilunga, a spokesperson for the Ministry of Health. The ministry has started tracing everyone who attended either the service or the funeral. The latter is particularly important: In Congolese traditions, friends and family members will touch, dress, hug, and even kiss the body of a loved one, providing routes for Ebola to spread. In this case, the deceased person was buried before they could be tested for Ebola.

This is the DRC’s ninth Ebola outbreak, and most of the others have hit remote areas. The last urban outbreak in the country happened in 1995, when the virus infected 317 people in the western city of Kikwit, and killed 245.

An urban case is always cause for concern, but it isn’t necessarily a disaster. Ebola is not an airborne disease. It can only spread through contact with infected bodily fluids, so effective hygiene and public health can still contain it in a densely populated area. During the DRC’s very first Ebola outbreak in 1976 (which was also the first one in the world), a sick nun was evacuated to a hospital in the megacity capital of Kinshasa, and even though nothing was known about the disease at the time, it didn’t spread. Similarly, in July 2014, Nigeria successfully controlled Ebola after it arrived in Lagos, Africa’s most heavily populated city; only 19 people were infected, and only eight died.

The latest figures from the WHO suggest that as of Tuesday, 44 potential cases of Ebola have been reported, including 40 in Bikoro and Ikoko, and 4 in Wangata. Of these, only 3 have been confirmed in laboratory tests: 2 in Bikoro and 1 in Wangata.

But new figures presented at a meeting on Thursday show that as of Wednesday, another suspected case has been identified in Bikoro, and 11 of the existing suspected cases have now been confirmed in lab tests. That gives a total of 45 cases across the whole outbreak, of which 14 have been lab-confirmed. The number of confirmed cases has gone up because a mobile lab is now up-and-running in Bikoro, rather than because the epidemic itself is progressing.

Lab tests are crucial since the symptoms of Ebola are not as horrific as commonly believed, and are often indistinguishable from more common diseases like malaria or typhoid. For example, the Mbandaka case was detected when a doctor in the city’s hospital noticed two patients with potential Ebola symptoms. A team from the Ministry of Health took blood samples and did rough diagnostic tests, which came back with two positive results. But when they sent the samples to the INRB for more rigorous testing, only one of them came back positive.

Both Mbandaka and Bikoro now have mobile labs, where researchers can test blood samples locally—a huge difference compared to most previous outbreaks. Provided by USAID, the labs contain generators, freezers, and equipment for doing diagnostic tests. The Mbandaka lab is expected to be operational tomorrow afternoon, once the WHO delivers a generator.

The entire country is now on high alert. On Wednesday, health officials in the Faradje, a town in the Haut-Uele province on the other side of the country, reported a suspected Ebola case and sent a blood sample to the INRB for testing. That may not mean anything. The Congo has a good surveillance system and “when you have an ongoing outbreak, the number of alerts will go up around the country because everyone is sensitive,” Mukadi says. “You’ll have 10 times more suspected cases than usual. We’re still waiting on the results and we hope it’ll be negative so we won’t have multiple epicenters.”

On Wednesday morning, the Ministry of Health received 5,400 doses of an experimental Ebola vaccine, which performed well in field trials during the recent West African Ebola outbreak. They are currently being stored in Kinshasa, and will be sent to Mbandaka when subzero storage facilities have been set up to receive them. The vaccine will initially be used to immunize health-care workers who have cared for suspected cases, people who have been in contact with confirmed cases, and others who’ve been in contact with them.

The vaccine’s very existence offers a new option for controlling the outbreak that wasn’t previously available. Had it been available earlier in the West African outbreak, “thousands of lives might have been saved,” said the Wellcome Trust’s director, Jeremy Farrar, in a statement. “Thanks to rapid national response and global collaboration, this time around we are in a better position to protect the communities at risk and the health workers dedicated to protecting lives.”

“But this will be an incredibly challenging operation,” Farrar adds, “and cannot be limited to deployment of vaccines.” Doctors Without Borders and its partners have set up small isolation zones and larger 20-bed Ebola treatment centers within Mbandaka’s and Bikoro’s main hospitals. Over the next few days, more than 26 tons of protective clothing, medical kits, isolation tents, and drugs for treating Ebola symptoms will arrive in Mbandaka.

Meanwhile, the WHO is sending around 30 experts to check for possible cases within Mbandaka, and is working with the Ministry of Health to engage with local communities on how to prevent Ebola.Change begins at the community level,” said Oly Ilunga, the minister of health, earlier this week. “Far from seeing themselves as victims, the whole community of Bikoro is mobilized and committed to defeating the epidemic of Ebola.”

“When the minister traveled to Bikoro last weekend, he was welcomed by traditional local chiefs, who said they were available to help raise awareness in the population,” says Jessica Ilunga, the ministry spokesperson. “That has always been the key part to the response to Ebola. As soon as we heard about the cases, the priority was to break the transmission chain by getting people to change their behavior.”

“Beyond responding to the actual outbreak, we’re also trying to make our health systems more resilient,” she adds. “We try to not send too many experts from Kinshasa. Instead, we’re training local health workers so that when the next outbreak comes, they know how to contain it more quickly.”

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