"We have a blank sheet of paper in front of us."
It didn't take long for Fabian Leendertz to discover this one noteworthy tree. It was near a riverbank in Guinea, a gnarled trunk, Leendertz thought: this could be exactly where the deadly Ebola epidemic of 2014 and 2015 in Africa started. It was detective work for Leendertz and his team, but the veterinarian has many years of experience: "The local authorities were able to ensure us that the epidemic started in the village of Meliandou. Children died there first," says Fabian Leendertz. He set out for the village. "The little children usually went with their mothers to wash by a small river, close to the tree." A tree ideally suited for children’s fun and games, it had a large hollow trunk and a hole to look out of. The residents told the researchers that a colony of bats had once lived there.
"We took DNA samples and determined that it must have been bulldog bats - a species that has previously been suspected of transmitting Ebola viruses."
The 48-year-old veterinarian and microbiologist has since returned to Germany and, as Founding Director, is now about to establish the Helmholtz Institute for One Health in Greifswald. The new task seems tailor-made for the scientist, who most recently led the Working Group for Epidemiology of Highly Pathogenic Microorganisms at the Robert Koch Institute in Berlin.
"Our approach is to examine the principles of pathogen transmission," says Leendertz: "What leads them to jump from animals to humans or from humans to animals? And based on this knowledge, how can we help protect humans, animals and also the environment?" The new institute is a unique opportunity, he says.
"We have a white sheet of paper in front of us that just says 'One Health'. It's now up to us to make our mark.”
You can hear his excitement when he talks about this new start. The first time he saw the connection between human and animal health with his own eyes was about two decades ago. At that time, he was on a field trip in the jungle of the Ivory Coast. The team of the famous Swiss behavioral scientist Christophe Boesch had been observing a group of great apes at a national park for decades. Leendertz joined them as a young veterinarian, and even today he raves about the year he spent in the jungle observing the animals. "It's like watching a soap opera on TV," he says, "the apes also have family bonds, they maintain animosities and friendships, there's always something going on." Until the day came when the soap opera turned into a drama. Fabian Leendertz was still at the researchers' camp early in the morning when a colleague reported that he had found a small chimpanzee dead in the forest.
"I did an autopsy right there on the spot, no external influences were visible,”
Leendertz says. He felt uneasy and suspected something was wrong. "The next day, researchers came running to me from the jungle, shouting, ’The alpha male is dead!’“. In front of their eyes, the chimpanzee had fallen over dead. "It became clear to me that this must be an infectious disease," Leendertz says. It later turned out that it was a new variant of anthrax. It remains unclear to this day where this bacillus came from. This was not the case for large outbreaks of respiratory diseases in the animals, where Leendertz was able to find the source: humans. That’s when Fabian Leendertz realised how important the field of One Health is.
About Fabian Leendertz:
The researcher's journey into the jungle began at the Zoo in Krefeld. Fabian Leendertz grew up in Nordrhein-Westfalen, the zoo’s director was a family friend. He spent days on end with the zoo director’s children between the enclosures and got to know a very different animal world to the one he had explored with his grandmother in the forest. "She was a hunter, one of the first women with a hunting licence back then," Leendertz says, "and she took me stalking through the woods and taught me a lot about nature." Much later, after finishing secondary school, he studied biology, which he quickly gave up - it was too much theory for him, he wanted to get closer to the animals.
So he started his studies in veterinary medicine, first in Budapest, then in Berlin. "I was interested in wild animals right from the start," he says in retrospect and smiles: "But during my studies I had to bite the bullet and work my way through dachshund diseases.” But while his fellow students were working on farms and in small animal practices, Fabian Leendertz went to Burkina Faso for an internship and did research on the tsetse fly.
Following the outbreak of the coronavirus, not only insiders are aware of the danger of zoonoses. Fabian Leendertz, who has already participated in a WHO mission to shed light on the mystery of the origin of COVID-19, knows that his new institute will be in the spotlight right from the start.
“What can we do to protect humans, animals and the environment?”
By Kilian Kirchgeßner, Issue 16/ November 2021/ Campus Magazin
