Monkeypox, lassa fever, polio – why viruses are attacking us
Sarah Newey investigates what is causing the sudden proliferation of deadly diseases in the UK
Gordon Richardson doesn’t remember the moment his legs failed. But he does remember the nine months he spent in hospital, wrapped in plaster from his armpits to his toes. “It was awful, I couldn’t move,” said Richardson, now 69.
When he was three, Richardson collapsed when saying goodnight to his father. It was the first sign he was infected with a virus that altered the course of his life: polio.
“Initially I had almost total paralysis, I only had use of my right eyelid,” he said. “Gradually I recovered the use of my head, neck, shoulders, most of my left arm and half of my right arm. But everything below my chest is basically paralysed… I’ve been in a wheelchair for 66 years.”
Polio, an incurable infectious disease which mainly affects children, was declared eradicated in the UK in 2003. Now, the wild virus circulates only in Pakistan and Afghanistan thanks to widespread vaccination campaigns.
But last Wednesday, the UK declared a national incident after experts sounded the alarm about the detection of vaccine-derived polio in London’s sewage system. A series of positive test results stretching back to February suggest there is ongoing transmission in north east London.
Polio is not the first dangerous and unusual virus to have arrived in Britain in the past six months. Aside from Covid, the UK detected a deadly strain of H5 bird flu in January, Lassa fever in February, Crimean-Congo haemorrhagic fever in March and monkeypox in May.
“There’s a name for what we’re seeing at the moment in the UK and elsewhere, it’s called chatter,” said Prof Mark Woolhouse, a professor of infectious disease epidemiology at the University of Edinburgh.
“It’s a term anti-terrorist [units] use to describe the small events that might signify something more major on the horizon… infectious diseases work in much the same way.”
The chatter is getting louder. Some are linked to heightened awareness of infectious disease post-Covid and strengthened surveillance systems, but experts – including America’s Prof Anthony Fauci – have warned of a “new pandemic era”.
Many of the factors driving the spread of new and existing viruses are not new.
Population growth, the booming economies of previously undeveloped nations, human encroachment into jungles and forest and the growth in the trade in wildlife have all played a part.
Climate change is also shifting the geography of disease. A paper earlier this year warned there could be a “potentially devastating” surge in the number of novel pathogens jumping between mammals over the next 50 years. It predicted “a minimum of at least 15,000” new spillover events by 2070, if temperatures rise by 2C.
“The early 21st century has been a perfect storm for emerging infectious diseases, and everything is pointing towards the likelihood of more and more outbreaks,” said Prof Woolhouse. “All the drivers of outbreaks are in fact getting worse, not better, over time.”
Some experts say the number of new diseases to have hit the UK in the past six months can also be linked to pandemic-related disruption, the easing of restrictions and a shift in migration patterns away from Europe post-Brexit.
Since leaving the European Union, non-EU immigration has boomed, with many more people coming from Asia and Africa.
“People going from this country to other countries and back is probably the biggest driver of disease importations,” said Prof Paul Hunter, a professor of medicine at the University of East Anglia.
“The UK is also one of the world’s leading transportation hubs,” adds Dr Richard Hatchett, chief executive of Cepi (Coalition for Epidemic
Preparedness Innovations). “And we have recently seen a surge of global transportation following two years of relative inactivity, enabling infections to spread rapidly.”
In February, a baby died from Lassa fever in hospital in Bedfordshire, one of three people to contract the haemorrhagic virus while in West Africa. A month later, a woman with a recent travel history to Asia was diagnosed with Crimean-Congo haemorrhagic fever, a related tick-borne virus with a fatality rate as high as 40 per cent.
The rapid worldwide spread of monkeypox – roughly 3,700 confirmed and suspected cases have now been reported outside endemic countries – is also linked to travel.
The first known case in the UK, where 813 cases have been reported, was linked to Nigeria. Many cases have since been linked to recent raves, sex parties and adult saunas across Europe.
“People travelling more freely again [post-Covid] – including for those in various sexual networks – may have boosted the ability of this virus to spread among a larger global population,” said Dr Julian Tang, clinical virologist at the University of Leicester.
In the case of polio, scientists are not yet sure how the virus reached London’s sewage system. But it is likely it came from one of a handful of countries still using polio inoculations containing a weakened version of the virus, as the strain detected is vaccine-derived. These include Pakistan, Afghanistan and several countries in Africa.
So what could come next? Some highlight diseases including flu – surging in Australia after being suppressed by Covid restrictions – and contagious viruses such as measles.
“Covid-related disruption to vaccination campaigns has also affected control of infections,” said Prof Adam Kucharski, an epidemiologist at the London School of Hygiene and Tropical Medicine. “Measles with its high transmissibility in susceptible populations means it is often the canary in the public health coal mine.”
‘All the drivers of outbreaks are in fact getting worse, not better, over time’
Meanwhile the potential arrival of the next “Disease X” is almost impossible to predict.
“We do need to pay attention, to strengthen pandemic preparedness and maintain our surveillance systems, because in the grand scheme of things Covid wasn’t as bad as it potentially could have been,” said Prof Hunter. “When it comes to disease, we’re not an island and it would be a mistake to consider ourselves as such.”
It’s a sentiment that Mr Richardson is fully on board with.
“I wouldn’t wish my disability on anyone,” he said. “We’ve got to deal with the UK’s vaccine derived polio cases quickly, so we can get back to focusing on the global eradication programme… I’ve love to see this horrid disease eradicated in my lifetime.”