“Get on that plane now! You know, they are crazy here!” shouts the manager of Kin Avia, a rare charter airline in the Democratic Republic of Congo with a decent safety track record. It is nearly 10am and for the past few hours we have been trying to get through all the formalities required to travel from the dilapidated domestic airport of Ndolo in the heart of Kinshasa to Bumba – in other words, to get through immigration for a domestic flight. Bumba is the nearest airport in northwestern Congo to our final destination, Yambuku, a village in Equateur province about 1,000km from the capital.

I am spending two weeks in the country to celebrate my 65th birthday and to thank the people who played such an important role in two defining experiences of my life: investigating the first known outbreak of Ebola haemorrhagic fever in 1976 and uncovering a significant heterosexual epidemic of HIV/Aids in 1983. I am here with an American film crew making a documentary on epidemics, along with my wife Heidi, an anthropologist, and my friends Jean-Jacques Muyembe, director of the DRC’s National Institute for Biomedical Research, Eugene Nzila, a pioneer of Projet Sida (Africa’s first big Aids research project, founded in 1984) and Annie Rimoin, an epidemiologist from UCLA.

When I was 27 and still in training, I had one of the greatest opportunities an aspiring microbiologist could dream of: the chance to discover a new virus, investigate its mode of transmission and stop the outbreak. It all started when my laboratory at the Institute of Tropical Medicine in Antwerp received a thermos from what was then called Zaire. It contained the blood of a Flemish nun who had died of what was thought to be yellow fever.

From that sample, however, our lab isolated a new virus, confirmed by the Centers for Disease Control in Atlanta and subsequently called Ebola, after a river about 100km north of Yambuku, the centre of the epidemic. It turned out to be one of the most deadly viruses known.

In early September 1976, Mabalo Lokela, the headmaster of the local school, had died with a high fever, intractable diarrhoea and bleeding. His death sent a shockwave through the small mission community. Soon the hospital was full of patients with a similar illness and nearly all died within a week.

This was the beginning of the first known outbreak of Ebola, a virus that is believed to circulate in bats, which accidentally infects people through contact with blood or infected droplets. There are four known subtypes affecting humans, including the “Zaire” type, the most deadly strain, with more than 90 per cent mortality. Transmission between people is through contaminated injections, contact with blood and body fluids, sex, and it probably passes from mother to child. Approximately one week after infection, patients develop severe fever, diarrhoea and vomiting. They then start bleeding and are affected by “disseminated intravascular coagulation”, whereby small blood clots develop in the body’s blood vessels, ultimately resulting in generalised organ failure, shock and death one week after the onset of symptoms.

Close to 90 per cent of the 318 people diagnosed with the disease would eventually die during the Yambuku outbreak. So would more than half of the hospital staff and 39 people from among the 60 families living at the mission. The entire region was devastated, with some villages losing one in every 11 inhabitants to Ebola.

Piot (second from left) on October 20 1976, the day of his arrival in Yambuku, together with fellow scientists and local health workers

Getting on a military C130 to Bumba in 1976 for the three-hour flight over the world’s second-largest equatorial forest was less complicated than catching a passenger flight in 2014, even though back then we had to load a Land Rover, medical equipment and barrels of fuel on to the cargo plane.

We were a Zairean, an American, a Frenchman and two Belgians in a plane – like one of those jokes. But the pilots were in a foul mood. They resented having to fly to the epidemic zone. Hadn’t fellow pilots told them that birds were falling from the sky over the forest around Yambuku and that dead bodies were lining the roads? When we landed, the plane came abruptly to a halt but the pilots never came out of the cabin. They didn’t even stop the engines. They wanted to take off again as soon as possible and avoid any contact with locals.

When I walked through the open loading dock at the back of the plane, I saw hundreds of people, staring at us in silence, followed by shouts of “Oyé! Oyé!” when we drove out the Land Rover. Ours was the first aircraft to break the quarantine that the whole region had been put under because of the epidemic and expectations were high that we would stop the disease, and bring food and medicines. As soon as the plane was unloaded, the pilots shouted “Bonne chance!” and off they went.

…

Bumba, the nearest town to Yambuku

This time there is a slight sense of déjà vu when we finally land on the red-earth airstrip of Bumba. The Congolese pilot recognises me from his time in the Zairian air force in the 1970s. “Has Ebola started again?” he asks anxiously.

Only a few people are at the airstrip, apart from the unavoidable immigration and security officers. One man is waiting for us just as he was in 1976: Father Carlos Rommel, the Flemish Catholic parish priest of Notre Dame, who has been working in the Congo for 51 years, mostly in Bumba. He had arranged all our logistics to perfection, just as he unflappably manages a hospital, a parish and four schools in a country where nothing can be taken for granted.

Our convoy of jeeps makes its way to the Bumba mission, where we will stay for the next few days, just as we did nearly four decades ago. Not much has changed – there is not a single paved road in this town of about 150,000 people and very few houses are made of brick or cement. This used to be a major port on the Congo River but years of war, looting and corruption have taken their toll. River boats are gradually returning – the 1,000km journey to Kinshasa can take up to six weeks in the dry season – always overloaded with people, cars and goods.

Despite being located on the mighty Congo, there is no running water in Bumba. Girls and women fetch water from the river, except in the neighbourhoods where Father Carlos has drilled wells. He seems to be the only real investor in infrastructure and social services in the city, sometimes using his own money. There is no electricity, besides what is produced by a lonely and noisy generator.

The first thing I see when visiting the public hospital is a large black truck near the entrance with “Morgue” painted across it. Not encouraging. Cattle graze between the pavilions. The hospital is largely empty as patients have to pay for everything and there are hardly any medicines, including anti‑HIV drugs and tests. For years, the state has not provided any support.

An aerial photograph of a typical settlement in the Yambuku area, taken on Piot’s first visit to the region

Together with Muyembe and Rimoin, two of the world’s leading experts on monkeypox, I see a nine-year-old girl who has contracted the disease from her brother. DRC has the world’s largest number of cases of this disease, which resembles the now eradicated smallpox, and is acquired from contact with various wild animals, not just monkeys. It is another illustration of how animal viruses can cause infections and even epidemics in humans (both HIV and influenza come from animals). In contrast to the public hospital, the mission-run Notre Dame hospital is clean and full of patients but even here there is a shortage of medicines.

Muyembe and I have lengthy conversations about the causes of this total neglect of people’s health and what we can do about it as academics. He repeatedly reminds us all of the motto of the University of Kinshasa, where he had been dean of medicine, and which was also the slogan of the Catholic high school of Bumba: “No science without conscience”.

…

Looking across the courtyard from our bedroom at the mission evokes one of the most dramatic moments of my stay in 1976. Early one afternoon, an Allouette helicopter (a gift from French president Valéry Giscard d’Estaing to Zaire’s president, Mobutu Sese Seko) arrived in Yambuku to take me to meet some high-ranking US officials in Bumba. As it was getting very dark, and I resented that these men did not want to come to where the action was, I decided not to fly. It saved my life – the helicopter crashed in the forest 15 minutes later and all three passengers died, including a worker from the mission who had taken my place in order to visit his family in Bumba. I always felt that poor man died for me.

Piot in Yambuku with nurse Sukato Mandzomba, who survived the initial Ebola outbreak

Three days later I had to recover the bloated corpses after a hunter found them, two hours’ walk from the nearest village through almost impenetrable forest. As there were no coffins, I had to make them myself at the mission workshop back in Bumba, which was the only place that had wooden planks. For years I could not talk about it and even now seeing a pile of planks at that workshop is extremely emotional.

Bumba, this morning, offers many distractions as well as memories but I am impatient to see Yambuku.

Road R337 is a red soil track through the green foliage of the dense equatorial forest. It is dry season and during a four-and-a-half-hour drive of more than 100km, we see two trucks full of goods and people, four motorcycles and many more people on or pushing bicycles, loaded with rice, peanuts, dried fish and bush meat, manioc, palm oil and bananas.

As we wend our way down the bumpy road from Bumba to Yambuku, I’m firmly holding on to a handle so as not to be ejected from the front seat and my head is spinning with memories of my first visit. The forest is a bit further away from the villages now, with trees having been cut down for fuel over the years, and there are far more children than I remember. There are also some new cement buildings in several of the villages we pass – often only one among the mud huts and Kingdom Halls of Jehovah’s Witnesses. There used to be palm oil plantations here, owned by Unilever, but these have been abandoned along with the paddy fields because of the wars and a deterioration in infrastructure and transport. With them went the last jobs, and many people are now living in a state of autarchy – fleeing into the forest for weeks at a time when various armed groups have invaded the area.

Piot is reunited with Father Carlos Rommel, who has worked in the Congo for 51 years

As we get closer to Yambuku the driver points to an overgrown area which was part of a village whose inhabitants had fled during the Ebola epidemic and never returned. Suddenly, the forest opens up and the road meanders through neglected coffee plants and bamboo before we finally see Yambuku. We are welcomed by sector chief Christophe Nzangolo, two doctors and four Congolese nuns, who have been waiting for us since noon on the terrace of the mission. Warm beer is served, formalities are exchanged and we are directed to our rooms. They are in dire condition, as is the rest of the building.

The Catholic mission in Yambuku was founded by the Order of Scheut in the 1930s with the support of a colonial cotton company in the then Belgian Congo. It was later joined by Sisters of the Sacred Heart of Mary. For many years, the village was a flourishing centre for education, healthcare and agriculture, and in some ways was a picture-postcard location.

But the 1976 Ebola epidemic, combined with a sharp economic downturn and serial wars, has led to a decline on all fronts. The mission was looted first by Mobutu’s soldiers and most recently by Bemba rebels, who were fighting the current government of Joseph Kabila and stole the ambulance and sideband radio, the villagers’ only means of communication with the outside world. (It took me a while to realise that the numerous small holes in the pillars of the convent’s terrace were actually bullet holes.) Since the departure of the Flemish nuns about 10 years ago, leaving some Congolese sisters, there has been no money available to replace or to maintain the vast convent buildings.

The austere guest house where we stayed was slowly imploding, children at the primary school were sitting and writing on the dirt floor, and the hospital was without drugs and had only a few mattresses. The powerful electricity generator we had left behind in 1976 was intact but lacked some essential parts, which together cost only a few hundred pounds. But the money was not there and, in any case, the sisters had no idea how to order the missing parts.

The school room where Piot and his colleagues slept in 1976

The jungle had invaded the once flourishing coffee plantations, which used to employ a significant part of the population. People now survive on what the fertile land, vegetation and wildlife can offer. In contrast to Kinshasa, there is no obesity in Yambuku and, according to the local doctors and as far as we can see, not much serious malnutrition either, in spite of a monotonous diet based on manioc, fried plantain and bananas, with occasional fish or bush meat.

Despite all the difficulties and lack of regular work, however, it is interesting to note how impeccably dressed the children and adults are. When we go for an early morning walk to enjoy some cool air before the steaming heat envelopes the village, we can see women sweeping the courtyards in front of their thatched-roofed mud huts, going to collect water and washing their children. These are among the world’s bottom billion, struggling to survive with what nature has to offer. They have just enough, but no spare capacity for an emergency.

…

When we arrived in Yambuku on October 20 1976, we went straight to the guest house, which sat between the nuns’ and fathers’ convents. Three European sisters and a priest were standing outside, with a cord between them and us. They had read that in case of an epidemic it was necessary to establish a cordon sanitaire, which they had interpreted literally. A message hung from a tree, saying in the Lingala language that people should stay away as anybody coming any closer would die, and to leave messages on a piece of paper. When the sisters shouted in French, “Don’t come any nearer! Stay outside the barrier or you will die!” I immediately understood from their accent that they were from near my part of Flanders. I jumped over the barrier, saying in Dutch, “We are here to help you and to stop the epidemic. You’ll be all right.”

They broke down, holding each other and clinging to my arms, crying. We could see the terror in their faces as they were convinced they too would soon die, just like four of their colleagues and a priest who had all succumbed to the Ebola virus in the course of a few weeks. Once we had all settled down, the sisters prepared a solid dinner of Flemish beef stew and started to tell the story of the epidemic. They explained in great detail how their colleagues had died, who the first victims were at the mission and then in other villages, and that nothing seemed to work as treatment. One sister had kept careful notes on each patient. They decided that we should sleep on the floor in the school classroom as we did not know whether the bedrooms in the convent were contaminated. But I didn’t sleep much that first night in Yambuku, with a thousand questions going through my head and the sounds of the rainforest outside.

Bikes left as pledges in Yambuku’s pharmacy

It quickly became clear that something was wrong at the hospital. Epidemiological detective work by our team confirmed the suspicions: people were being infected at the hospital through injections made using contaminated needles and syringes (only five syringes and needles were issued to the nurses each morning), and hospital staff and attendees at funerals were falling victim through exposure to body fluids infected with the virus. In addition there seemed to be transmission from mothers to babies.

Closing the hospital (which, in any case, had been abandoned by frightened patients) was the decisive action that stopped the Ebola epidemic, and the last victim died on November 5. In simple terms, poor medical practice had killed hundreds of people. The missionaries were undoubtedly doing highly valuable work in education and community development but managing a hospital (without a physician, since they could not find one who would work in such a remote place) was beyond their expertise.

On December 16 1976, the quarantine was officially lifted after four long months. The military transport plane that came to pick us up with our precious samples, lab equipment and Land Rover was the first contact with the outside world since we had arrived three months earlier. It was nearly stormed by people who wanted to leave the area.

The village graveyard

I had a heated argument with the pilots, who were filling the plane with rattan furniture that belonged to General Bumba, their big boss, and allowing other people who had bribed them on to the plane. There was hardly any space left for us and our goods. Nothing could be taken for granted in Zaire! I argued and swore and joked, and in the end we all got on the aircraft. I suddenly realised I had become assertive.

That was not the end of the story. The Buffalo plane was overloaded, as well as badly loaded, and the pilots took off straight into a formidable tropical storm. We touched the top of some trees and before reaching cruising altitude the plane dived for what felt like a few hundred metres. There were no seat belts and we were hit by heavy flying boxes. Eventually we made it safely to Kinshasa but my legs were trembling when we got out of the plane. For me, flying had been more dangerous than caring for patients or handling virus samples.

…

Decades later, it is a great joy to see Sukato Mandzomba slowly walking towards me. “How are you?” he asks simply. “How is the family? My wife and I are so happy you came back.” He is smiling shyly and as if we had seen each other just a few days ago. Sukato is one of the few survivors from the 1976 Ebola epidemic. As a 24-year-old nurse, he was infected while caring for dying patients with haemorrhagic fever but never developed the severe, fatal form of the infection which causes massive bleeding and shock. Sukato was among the first people we saw on our arrival in Yambuku in 1976, and after he had recovered from his illness he volunteered to look after patients and helped us with our clinical and epidemiological work.

Piot with Sukato Mandzomba in the latter’s makeshift laboratory in Yambuku

He now runs the rudimentary hospital laboratory, with a microscope and a hand centrifuge as his only equipment. Typically for Sukato, the laboratory logbook has impeccable records, and he shows me the characteristic bacilli in the sputum smears of numerous tuberculosis patients.

The hospital looks the same as I remember it but with far fewer patients, even if there is now a competent doctor. The main reasons for people staying away are the lack of affordable drugs (the government has not sent any for more than two years) and extreme poverty prevents them from paying the various fees that are charged in the absence of any health insurance scheme. Medicines are bought at the weekly market in nearby Yandongi and then sold at a profit to subsidise the hospital.

In the tiny hospital pharmacy we see six bicycles, palm oil and a few bags of rice, left as security by patients who could not pay for their drugs. The Yambuku “health zone” covers 14,000 sq km and 260,000 inhabitants but has no ambulance, no means of communication, hardly any medicines and just one fridge for vaccines. The two doctors and the nurses are trying to find solutions without any support from their government or the international community. Many would have given up but they are beacons of professional commitment and dignity amid abject poverty, the state having abdicated all responsibility.

Piot with Mandzomba on a return visit in 1986

Since that first visit, there have been more than 20 outbreaks of human Ebola haemorrhagic fever, all in Africa, except for a few laboratory-acquired cases. This year, and for the first time, Ebola virus caused a multi-country epidemic in west Africa that originated in Guinea-Conakry. Humans are an accidental host, as a virus that kills its host in a couple of weeks could not survive in nature. It is not clear how the virus reached this part of the continent though its genome has been found in a fruit-eating bat in Gabon.

In general, Ebola is a disease of close contact with wildlife, of poverty and particularly of dysfunctional hospitals, which can become deadly centres of viral spread through unsafe injections and lack of basic hygiene. Healthcare workers are usually the first and most affected population. In principle it is very easy to contain an Ebola outbreak: with gloves, hand-washing, safe injection practices, isolation of patients, safe and rapid discarding of the corpses of those killed by Ebola, and tracing of contacts and subsequent observation for a few weeks. In reality, the health infrastructure where Ebola strikes is usually very poor and panic often leads to dissemination of the infection, with people fleeing affected areas, as is the case now in west Africa.

As long as health services are inadequate, there will be occasional outbreaks of Ebola in parts of Africa where the virus is hiding in some animal. In theory, there is no need to send in numerous outside experts as control measures are very simple and inexpensive and can be implemented by local professionals and volunteers. However, the reality is that because of their high mortality rate and contagious character, as well as today’s mobility of people across borders, outbreaks due to Ebola and other dangerous viruses must always be considered as a global threat, amply justifying international support and research. The cost of public panic and societal disruption can be enormous, with healthcare workers disproportionately affected – going far beyond the actual impact in terms of deaths due to Ebola.

…

My last visit to Yambuku had been in 1986, 10 years after the first Ebola epidemic. Along with colleagues from the US Centers for Disease Control, we tested the blood samples we had collected in 1976 for HIV antibodies and found that 0.8 per cent were infected – five years before the first reports on Aids were published in the US. I had gone back to find out what had happened to the individuals who were HIV positive and also to explore whether that other virus in my life had spread further in the region. We found that three had died but also that two men and women had been living with HIV for at least a decade and appeared fairly healthy. The level of HIV infection in the population at large was still 0.8 per cent though it was as high as 11 per cent among prostitutes in the region. Around the same time, HIV prevalence among adults in Kinshasa was as high as 6 per cent (today HIV prevalence in the capital has declined to 3 per cent).

The four nuns killed in the initial oubreak

Our research showed not only that people can live for at least 10 years with HIV but also that the virus had existed at low levels for many years in central Africa. Together with later genetic studies of HIV isolates from all over the world, and the discovery that chimpanzees can be infected with a virus very closely related to the human immunodeficiency virus, these findings helped elucidate the origins of HIV.

…

On our last day in Yambuku, the film crew wants to interview me on the front porch of the convent. It is now barricaded for security reasons but when I was here during the outbreak, this was my favourite place to work and reflect while I watched people strolling by.

It is with mixed feelings that I have to leave this beautiful place and people. A dream I wrote about in my memoir has come true: I have come back to Yambuku, to “Ebola ground zero”, a place and experience which changed my life. But I am left with many unanswered questions: how do people live, survive and die here? And what are their aspirations for their children? It is upsetting to see the deterioration in living conditions and infrastructure, reducing people to their most basic condition humaine.

The Ebola virus photographed in 1976

As I sit next to Father Carlos on the return trip to Bumba, I ask what drives him. He says his real religion is fighting poverty and injustice. Then suddenly he turns to me and says: “You challenged me in 1976: why did I not do more for the daily life of the people of Bumba, besides all the religious activities? That is when I decided to start a hospital. You really turned around my life.” It is stunning that I had had any influence on a priest but it is also a profoundly happy moment.

Two days later, back in Kinshasa, we take our first real shower in a week before going to a concert by superstar Papa Wemba, together with more than 20 former colleagues with whom I had worked on Aids in the 1980s and 1990s in Projet Sida. As always, I find the rumba and soukous liberating. The vitality expressed in Congolese music reflects the creativity and love for life of the Congolese people. They deserve better than their daily struggle for survival. New viruses will unavoidably continue to emerge, particularly where people and animals live in proximity but war, greed and corrupt governance are man-made disasters, and they can be prevented.

Peter Piot is a microbiologist and physician, and director of the London School of Hygiene & Tropical Medicine. His book, ‘ No Time to Lose: A Life in Pursuit of Deadly Viruses’, is published by Norton.

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