Humans have been at war with microbes for millions of years, and they aren’t giving up the fight any time soon. Pathogens are constantly changing, evolving with altered characteristics, which presents new challenges to science, healthcare and society. From tracing new outbreaks to developing novel vaccines in a timely way, we must always be on our guard for the next threat.
Within a matter of months of its first appearance in China in late 2019, a novel coronavirus had spread around the globe, upending conventional life and causing the illness, COVID-19, in millions of people. As world leaders grapple to find the best way to respond to this threat, it reminds us that we cannot predict when, where, or what the next infectious epidemic will be. We need to be as ready as we possibly can be to respond to emerging diseases and roll out vaccines to protect against them.
The 2013-16 Ebola outbreak in West Africa caused more than 11,000 deaths and cost at least $50 billion. Rapid vaccination at the right time and place would have made a huge difference: although a vaccine against the disease had been in development for more than ten years, it wasn’t ready to roll out until the epidemic had spread for a year, costing many thousands of lives.
Diseases do not respect borders, so protecting the world’s population requires an international effort. The Coalition for Epidemic Preparedness Innovations (CEPI) is a global alliance that funds and coordinates the development of vaccines against emerging infectious diseases, and enables access to vaccines during outbreaks. Prior to the COVID-19 outbreak, CEPI had secured more than $750 million in investment from many governments and charities, including the UK Government and the Wellcome Trust. In March 2020 the UK Government pledged another £210 million towards the development of vaccines against COVID-19, making the UK the largest individual donor to the coalition.
CEPI is pushing new vaccines through initial safety testing and early-stage clinical trials in order to build a stockpile that is ‘good to go’ before an epidemic even begins. CEPI is also funding innovative platforms that can accelerate the development and manufacture of novel vaccines in a matter of months rather than years, and working with governments and regulatory agencies to make sure that they can get to the people who need them most.
Are we ready for ‘Disease X’?
The World Health Organization uses the term ‘Disease X’ to refer to an as yet unknown pathogen with the capacity to cause serious harm to human health. It is understandably hard to predict where any new disease will come from, but we can still do much to build the skills and capacity to respond rapidly when it does.
Consistent investment in immunology and vaccines is the best way to prepare for the next epidemic, but once an outbreak is out of the headlines, the funding for research often dries up. Although it has spread with a lethal ferocity, SARS-CoV-2, the coronavirus responsible for COVID-19, isn’t a complete surprise to science. Durin
the SARS outbreak in 2002-04, caused by a coronavirus similar to SARS-CoV-2, several vaccine candidates were identified but the research petered out when the epidemic died down. If research had continued, we might have been better prepared to tackle the related COVID-19 pandemic.
Over the last five years we’ve been on a path to expand our capacity for protecting against many of the pathogens that we recognize as threats to global health. One of the things we really need to do going forward is to work out the pathway from the brilliant vaccine discovery work that has happened in the UK all the way through to having products that are licensed and ready to go when they’re needed - Professor Andrew Pollard, University of Oxford
Researchers in the UK and around the world are now racing to develop new vaccines for COVID-19. But it won’t be enough to make and test novel vaccines in experimental settings. Indeed, several vaccine candidates are building on the work that was done after previous outbreaks of related coronaviruses, SARS and MERS. Promising products need to be fast-tracked through clinical trials and regulatory approval without compromising on safety or efficacy - even in the midst of a pandemic - and produced on a large enough scale to immunise entire populations.
There has traditionally been little commercial incentive to develop vaccines for diseases affecting populations in small geographic areas in developing countries, or those that only occur in intermittent outbreaks. But in our modern, interconnected world, disease outbreaks in other countries can end up affecting us all, so we need to make sure we’re ready to face whatever the future brings.
Making the jump
Most of the recent infectious diseases that have evolved into pandemics originally came from animals. For example, HIV first originated in chimpanzees, while Ebola is thought to have been transmitted to humans from bats. Although the exact animal source of the latest SARS-CoV-2 coronavirus is currently unknown, it is also thought to have originated in bats. Recent global shifts including climate change, habitat destruction, increasing human populations and illegal wildlife and bushmeat trades all make it more likely that pathogens will have the opportunity to make the jump from animals into humans.
There’s a vital role here for surveillance and monitoring of human and animal populations in ‘hot spot’ countries in Africa, Asia and South America in order to spot emerging threats. For example, the Zika virus was first identified in African monkeys in 1947, sixty years before the first widespread outbreak in humans. It’s therefore equally important that these concerns are reported to and acted upon by national and international health authorities in a timely way. Failure to do so risks the emergence of other diseases with the potential to escalate to pandemic status, resulting in widespread loss of life, economic damage and geopolitical destabilisation.