UK Edition
Could you be a virus super-spreader?
Here’s the scary thing: it isn’t a matter of if it will happen, but when. At some point in the future – possibly the very near future – Britain will be hit by a deadly pandemic, and its impact could be utterly devastating.
We probably won’t immediately know it when it arrives, either. It might come as a new strain of the influenza virus passed from animals to humans, such as in the case of avian and swine flu; it might come from the rumbling threat of bio-terrorism; or it might be a pathogen no scientist has ever seen before, like the mysterious ‘Disease X’ the World Health Organisation convened to discuss in February.
Whatever it is, 100 years on from the start of the Spanish Flu – which took little more than a year to claim four times the number of lives as World War One – the risk of a similar outbreak is alarmingly high. And in the absence of correct planning and counter-measures, the likelihood of it spreading and killing millions of people around the country is very real.
Reassuringly, at the moment the UK government ranks pandemics as a “serious threat” to our national security, and there are enormous warehouses solely reserved for stockpiling equipment and provisions for the public’s safety, as well as numerous doctors and scientists whose only job is to try and develop vaccines for when it hits. Over the past two weeks, too, footage and photographs of specialist police officers and hazmat-suited experts shuffling cagily around the streets of Salisbury may have been chilling, but it has at least shown that we have invested in bio-hazard research and preparedness.
But the threat of a pandemic is different from that of a nerve agent, in that a disease can spread uncontrollably, long after the first carrier has succumbed. Quite how that spread would occur has previously been limited to vast assumptions based on surveys and small data sets, leaving us open to finding out as and when it happens.
Now, though, thanks to a huge citizen science experiment a team of experts and I conducted for a new BBC documentary, Contagion! The BBC Four Pandemic, we’ve given ourselves a powerful weapon in the fight against the disease. A way to find out exactly how a real pandemic might unfold.
The premise was simple: we’d infect the good people of Haslemere, a lovely town off the A3 in Surrey, and wait and see what happens. Health and safety laws and BBC compliance bods wouldn’t permit the real thing, of course, but fortunately we the public carrying the ideal device to carry out a large-scale research project like this. One that’s portable, permanently glued to (most of) us, and fitted with a built-in GPS trackers – our phones.
Using a newly-built app to ‘infect’ users, we decided to track where participants went and who they interacted with over the course of a few days, allowing us to view not only how quickly a potentially deadly virus spreads in a local area, but who the most dangerous carriers were. Then, if enough people around the country could be convinced to also download the app, our researchers at the University of Cambridge could use the data gathered to create a simulation of how that virus might then move around the UK. As a mathematician, it was a intriguing prospect, but it was also potentially life-saving.
Haslemere wasn’t chosen by accident. As well as being the right size to manage the experiment, it’s no more than an hour from Britain’s two biggest airports and an easy drive to the major sea ports of Portsmouth and Southampton (probability-wise, a pandemic would almost certainly originate from overseas); it also has a traditional, bustling high street; and a train station with regular commuter services to London. In short, it's is the ideal place to test how far a deadly virus could get.
Electing myself as Patient Zero – the term often used to describe the person identified as the first carrier of a contagious disease – I spent a day wandering around Haslemere, where hundreds of people all over town had the app downloaded. Even with a deadly flu, you can spend a day being infectious but without any symptoms, and I acted in that way: I went to a yoga class, did a bit of shopping, had lunch in a cafe, and finished the day with a pint in the local pub. No forced movement into crowded places, no prolonged stays anywhere, just a normal day.
The results were very worrying. Like a giant game of ‘it’ in the playground, I got nine people in around 8 hours of mooching. They in turn spread the virtual virus to 69 more. By day three, more than 500 people were infected, all over the map of the town. And once we expanded that nationally, it quickly became millions.
It was an exponential spread, and seemingly uncontainable no matter what measures we took. Yet in analysing who infected the most number of people, we uncovered evidence of something which could end up saving a lot of lives.
In every community, there are a number of ‘social super-spreaders’ among us. Long-suspected and emphatically confirmed by our data, these are people who – through dint of their job, or lifestyle, or perhaps even genetic makeup – would be more dangerous in the instance of a pandemic than the average person. In Haslemere, for instance, our biggest super-spreader was a lady who worked in a hardware shop, but it could be school teachers, train staff, paramedics, waiting staff... anybody who has close contact with high numbers of people every day.
The discovery is potentially very significant. By being selective and strategic with limited medical supplies, we can target vaccinations to the people we identify as super-spreaders, which could cut the speed of a virus spreading around the country so dramatically that it's the difference between a problem and a catastrophe.
But what about the rest of us, what can we do to avoid the contagion? In a flu outbreak, the government’s advice of ‘catch it, bin it, kill it’ (using a tissue when you sneeze, then binning it, then disinfecting your hands) could make a staggering difference, but no place is necessarily better than another during a pandemic. It’s probably best to just hunker down where you are. If you travel to ‘safe ground’ you’re risking transport and moving to a new environment; if you search for the company of family, how do you know you aren’t giving something to them?
Fortunately, we aren’t just guessing any more. A century ago the Spanish flu confounded scientists and devastated whole regions, but while today’s society has air travel and an enormous, heterogeneous population, we also have antibiotics, fantastic communication networks and, perhaps most crucially, more data than ever.
On Thursday, for example, researchers from the University of New South Wales released results from a mathematical model developed to predict how many people would become infected if weaponized smallpox was unleashed in New York. The death toll ran into the thousands, which is a wake-up call, given Russia is thought to possess smallpox samples. If history hasn’t taught us to be worried, perhaps recent events will.
It’s research like that and our BBC experiment that will inform policies that could save many lives. Numbers are a powerful weapon, and the data we’ve gathered sets a new gold standard, helping governments around the world hone their response to a crisis at once unknowable and inevitable. And that's quite a combination.
Contagion! The BBC Four Pandemic is on BBC4, Thursday at 9pm
As told to Guy Kelly