PieterMorlion via Wikimedia Commons (CC BY 2.5)
Fifty years ago, Professor (now Baron) Peter Piot, emeritus director of the London School of Hygiene and Tropical Medicine, was a final-year medical student exploring options for a research career. He was advised that ‘there was no future in infectious diseases’ as, thanks to public health improvements, vaccines and anti-infective drugs, the most important and interesting problems there had been solved. Thankfully, he took no notice of that advice because nothing could have been further from the truth. Only a few years later he was directly involved in the discovery of the Ebola virus. His distinguished career since has, essentially, been a battle against the three ‘intertwining pandemics’ of the last half-century: Ebola, HIV and, of course, COVID-19.
The ongoing battle against infectious diseases
The early history of the COVID pandemic is a stark illustration of the way that infectious disease can throw curveballs. Before that virus emerged, it was widely assumed that a new pandemic disease was most likely to be a type of flu. The 2008 version of the UK’s National Risk Register even declared a flu pandemic to be ‘the gravest threat to the UK’s security’. Our government’s ‘Exercise Cygnus’ in 2016, a massive role-playing exercise planning for such a pandemic, contributed to the UK’s high ranking in the World Economic Forum’s pandemic preparedness rankings in 2019. We all know how that turned out; flu and COVID might both be respiratory viruses, but precautions against one cannot be expected to work for the other.
So how do you prepare for something when you don’t know what form it will take? Enter ‘Disease X’: a shorthand for the next pandemic disease ‘whatever it might be’. The World Health Organisation coined the term in 2018 and has included it on its lists of ‘priority pathogens’ since then to represent the unpredictability of disease threats. When a seriously threatening pathogen does emerge, the term will be rapidly switched to ‘the next one’ so it remains hypothetical: COVID-19 itself was briefly ‘disease X’ until it was named.
Nita Madhav, Senior Director of Epidemiology and Modeling at Ginkgo Biosecurity, part of the US-based biotech company Ginkgo Bioworks, recently told the One Health Trust that she estimates a 2-3% chance that a significant pandemic will emerge in any given year. Recently, the world has dodged bullets with diseases that spread but proved to be mild: such as the 2009 swine flu pandemic; that killed many of those infected, but didn’t spread: such as the original SARS; and that could be contained: such as Ebola. In fact, she said, you could also include COVID-19 with its comparatively low mortality rate in that list: it might be best described as a ‘wake-up call’. The millions around the world who are suffering from Long Covid are unlikely to agree.
Strategies for global pandemic readiness
So, the next Disease X cannot be far away. It may be another respiratory virus, but there are frighteningly many other possibilities. Bubonic plague, which killed a larger percentage of the world population than any pandemic before or since, was caused by Yersinia pestis bacteria, and antibiotic resistance is increasing the chance that a novel, untreatable bacterial disease will emerge. It might even be a fungal disease.
Thankfully, there are many things that we – governments, the clinical and research communities and concerned citizens – can do to make sure that we are as ready as possible for whatever Disease X might throw at us next. A (probably non-comprehensive) list might include:
- Supporting health research that prioritises the diseases of the Global South, principally infectious diseases, and fair access to treatments within and between countries: and supporting parties that include these policies in their manifestos.
- Exploring, as far as we can, how the current model of pharmaceutical research might be changed to prioritise these conditions and make drugs and vaccines available and affordable to all. The WHO’s collaborative, not-for-profit research hub in South Africa, which is researching mRNA vaccines like the Pfizer and Moderna COVID-19 vaccines, is a very good example and this could, at least in theory, be rapidly switched to developing vaccines for any emerging viral disease.
- Maintaining and increasing infectious disease surveillance during and, particularly, outside health emergencies, so anything unusual can be picked up straight away.
- Supporting vaccination, as citizens: by keeping up to date with every vaccination that is offered; as policymakers: by improving availability of and access to vaccines; and as scientists and clinicians: by prioritising research into novel and improved vaccines.
Research in East Anglia
So, what is happening in our region? Researchers at the Department of Pharmacology in Cambridge University, led by Mark Howarth, may be showing the way. They are researching a new vaccine platform that could be expected to protect against a wide range of coronaviruses: nowhere near a universal vaccine for respiratory viruses, but a good start.
It is vanishingly unlikely that infectious diseases will ever return to the research backwater that the young Peter Piot was warned against in the 1970s. Disease X and its successors will have many tricks up their sleeves, and we will need to be ready to counter them.
