But while pre-pandemic lists focused on a narrow set of around a dozen priority diseases, the latest blueprint includes well over 30. It also creates a set of prototype pathogens for 22 major families of viruses, in an attempt to replicate the success seen with Mers and Covid.
Dr Hatchett said this updated approach was not so much a reflection of a major shift in the underlying risk each disease presents, but an evolution in the thinking of the scientific community about how best to prepare for pandemic threats.
“By getting to know as much as we can about each of the pathogen families that are most likely to harbour the next pandemic-causing disease, scientists can get a head start in creating new medical defences such as vaccines and treatments that can be swiftly adapted to target a new disease,” he said.
“Think of it as a jigsaw, with each family representing a part of the puzzle. The new pathogen family framework maps out each of these families and will help to coordinate the efforts and resources of institutions around the globe… and put the pieces together to solve the problem of pandemics for the world.”
Speaking at the Global Pandemic Preparedness Summit in Brazil at the end of July, the WHO’s Dr Ana Maria Henao-Restrepo, who co-leads the project, used a different analogy: the ‘streetlight effect’.
“This is the metaphor of the drunken man looking for the lost keys under the streetlamp. The first place where the drunken man is going to look for his keys is under the light. The light areas are the pathogens for which we have a lot of information today, we know that they are global threats… but we want to expand that light area,” she said.
“So one way to expand… is [to use] prototype vaccines which are pathfinders, who will help us develop medical countermeasures that maybe can be useful for other pathogens in the same family.
She added: “So we are now promoting research in all the viral families, regardless of the pandemic threat potential that we perceive today, because the pandemic threat potential that we perceive today is based on the data and the knowledge that we have today.”
To further this strategy, the WHO has also announced that institutions across the world will become central hubs (dubbed a Collaborative Open Research Consortium, or Corc) for different pathogen families, leading and coordinating work between partners – from funders to researchers and regulators.
But Dr Henao-Restrepo added that it is “improbable” that the next pandemic will be caused by a disease we know – which is why experts must still plan for Disease X.
“The concept of pathogen X… says there is uncertainty, and there are pathogens in these less illuminated, less studied areas that we still need to pay attention to,” she warned.
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