Nathan Wolfe travels to viral “hotspots” to find dangerous viruses before they go global. He talked to Linda Geddes about why we are more vulnerable than ever to a deadly pandemic
You advised on the film Contagion, in which a lethal virus spreads across the globe within weeks. Do you think that kind of scenario could ever become a reality?
It is very possible. It’s easy to forget that the world is still in the midst of an incredibly harmful pandemic – HIV – which emerged by jumping from animals to humans and is spreading around the world.
Will a future pandemic look exactly like the Contagion scenario?
No, but if you’re going to make a fictional depiction of this sort of thing, you have to choose one scenario.
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What would you do if a pandemic like that happened?
Because of the work I do, I’ve been immunised against just about everything you can imagine being immunised against. But if one of these things happened, I would be right in line with everyone else getting vaccinated.
You set up (GVF) to spot potentially dangerous viruses before they infect significant numbers of humans. Why take this approach?
If you look at swine flu, it spread so effectively, despite humanity’s best efforts, that it infected an estimated 10 per cent of the human population within a year or so. We just got lucky that nature handed us a virus that was not particularly deadly. It wasn’t our response which really made a difference.
At GVF, we are watching as viruses cross the portal between animals and humans – the birth of pandemics, if you will. Understanding this interface and capturing the diversity of viruses on both sides is very important to our work, because once a pandemic has happened, it is very difficult to address.
Are there certain places in the world that deadly viruses are likely to come from?
We believe that there are viral hotspots. They tend to be in locations with a high diversity of wild animals, where there’s high contact with humans and also close proximity to transport networks and large populations. That is why we’re particularly focused on central Africa, and south-east Asia.
How do you spot the birth of a pandemic?
We think that one of the most important risks is contact with wild animals. We’ve spent a lot of time in places such as central Africa working with hunters and finding out the diversity of viruses that are present in the animals and the ones that are chopping into human populations. Taking blood samples from hunters to see what viruses they are infected with is one example of this.
What is the most significant discovery that you have made?
Over the past 10 years we have documented a range of novel retroviruses that have jumped from animals into humans in our studies in central Africa. That viruses in the same family as HIV cross regularly into humans was surprising. It means that the events that led to the HIV pandemic were not some sort of one-off.
Bushmeat is a risk factor. Have you ever eaten it?
Yes. I lived in central Africa for five years. There’s plenty of bushmeat that I don’t think is a huge risk. I’ve eaten a whole range of wild game from snake to porcupine. Like any source of animal protein, when prepared well it can be tasty. Porcupine certainly can taste very nice – a little like rabbit.
Do you think we are at greater risk from pandemics as the world becomes more interconnected?
Yes. If you go back only a couple of hundred years, these viruses would wander through a small group of individuals and then go extinct. Now they have an increasingly global stage on which to act. We have viruses that spread around the world continuously, and by the time they get back to the beginning they have new people to infect, or the virus has changed sufficiently that the thing gets to live almost indefinitely within humans. That’s not the way that it worked in the past, and our vulnerability is really, really substantial.
“Viruses now have a global stage on which to act. Our vulnerability is substantial”
Are you hopeful that we can stop potential pandemics?
I tend to be optimistic. Certainly the world is changing dramatically and there are advantages for these agents, but there are also factors, such as the connectivity we have in terms of communication, that give us new ways to address them. But we’re not going to be able to just dodge bullets left and right, and ignore the source of the bullets, which is what we do when we ignore the importance of an event like swine flu.
Some people have said that swine flu was hyped up. What do you think?
I don’t think it was hyped up at all. Infecting 10 per cent of the human population and killing 100,000 people globally: that was a very important biological event. And it certainly could turn more deadly. These viruses have an incredible capacity to mutate and combine genetic information with other viruses. That can fundamentally change their properties.
What do you think is the greatest viral threat at the moment?
There are certain risks that we are very vulnerable to these days, including some of the small RNA viruses such as flu and SARS – things that have the capacity to change very rapidly. From studying the history of these, we can be almost certain the biggest risk is a virus jumping from an animal. It’s probably going to be something we haven’t seen before, and because there are so many things out there, the potential to be blindsided is very high.
Do you have a favourite virus?
I don’t know if it’s my favourite, but look at rabies. This is a very small RNA virus, at the smallest point you can get to in terms of the amount of genetic information it needs to exist as part of the living world. Yet it has the capacity to take over things orders of magnitude larger, be it a bat, a dog or a human, and alter fundamental features of their physiology to assist it to replicate.
Increased aggressiveness is one way rabies alters behaviour in order to facilitate its transmission. It is an incredible drama, the way in which it is able to function.
What keeps you awake at night?
As a species, we’re not that focused on the things that have the most potential to be devastating to us as a global population, such as viruses. Unless people take these things seriously, we’re going to look back and say we had all the tools necessary to try and address these risks, and we basically ignored them because they weren’t dramatic like a car accident or a hurricane.
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is professor in human biology at Stanford University, California, and founder and director of , an independent research institute devoted to the early detection and control of epidemics. His book, , is out this month (Times Books)