A new study from the MRC-University of Glasgow Centre for Virus Research has found that COVID-19 immunity has offered protection against a new coronavirus pandemic.
The study, published in Nature Communications, found that global immunity to COVID-19 is likely to lower the risk of an emergence of an as-yet undiscovered new SARS-type virus, dubbed SARS-CoV-X, ultimately lowering the risk of a future coronavirus pandemic.
The scientists utilised real-world patient antibody samples, along with mathematical modelling, to gain a better understanding of immunity levels against SARS-like viruses across the global population.
They discovered that, in addition to high levels of specific immunity to SARS-CoV-2, the virus responsible for the COVID-19 pandemic, the population also exhibited cross-protective immunity against a variety of sarbecoviruses, which are part of the broader family of viruses to which SARS-CoV-2 belongs.
Infections by endemic viruses—viruses that circulate commonly in the general population—and the vaccines used to control them often provide cross-protection immunity against related viruses.
This cross-protection can potentially alter the transmission dynamics of new zoonotic viruses with pandemic potential and even the likelihood of their successful emergence.
Professor Pablo Murcia, Professor of Integrative Virology from the MRC-University of Glasgow Centre of Virus Research, said: "Our global experience with COVID-19 has generated a biological barrier to other coronaviruses."
"While this does not mean we are immune to all future threats, infection and vaccine-derived immunity to SARS-CoV-2 has made it much harder for other sarbecoviruses to start the next pandemic."
Our study shows the circulation of SARS-CoV-2 in the general population, alongside global vaccination campaigns, generated widespread immunity against related sarbecoviruses, creating an 'immunity shield' against the emergence of a novel sarbecovirus in humans.
The researchers also showed that preventive vaccination campaigns against any potential new sarbecovirus, SARS-CoV-X, using currently available COVID-19 vaccines could help slow or stop the global spread.
Brian Willett, Professor of Viral Immunology at the CVR, added: "Our results suggest that our current vaccines might be effective against the emergence of a new coronavirus."
Our mathematical models strongly suggest that the use of existing COVID-19 vaccines against any new and emerging sarbecoviruses reduced the chance of sustained transmission.
"We found that current vaccines would be most beneficial if implemented soon after the first SARS-CoV-X case was found. By contrast, delays in implementing any preventative vaccination would likely reduce its effectiveness."
Identifying zoonotic viruses before they emerge is crucial for pandemic preparedness. To infect humans, these viruses must overcome biological barriers, including the ability to sustain human-to-human transmission. A significant challenge is overpowering existing immunity within the population.