Every year, the race begins anew. Scientists scramble to track mutating viruses, pharmaceutical companies reformulate vaccines and public health systems brace for another season of jabs and logistics.
Author
- Antony Black
Lecturer, Life Sciences, University of Westminster
This relentless cycle is our frontline defence against threats like flu and COVID - but it comes at a steep price. Globally, billions are poured into strain and variant surveillance, vaccine development and distribution, leaving already-stretched health systems - particularly in lower-income countries - struggling to keep pace.
That's why scientists have long aimed to develop universal vaccines - ones that protect against all major forms of a virus, including both seasonal and pandemic types. But designing these vaccines has proved to be tricky.
The difficulty lies in the way viruses mutate. Influenza and SARS-CoV-2 (the virus that causes COVID) change rapidly, allowing them to escape the immune system's memory responses triggered by past infections or vaccinations. To make a universal vaccine, researchers must identify parts of the virus that stay the same across different strains and variants - known as "conserved regions".
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These conserved regions are harder for the immune system to recognise, so scientists are developing strategies to enhance the body's response to them . One approach removes the rapidly mutating parts of the virus from the vaccine entirely, helping the immune system focus on the parts that don't change.
Another strategy involves "mosaic" vaccines , which combine elements from many virus strains to trigger a broad, protective immune response.
Several technologies used to deliver these vaccines are at various stages of development. For example, mRNA vaccines use lab-made strands of messenger RNA (a type of genetic material) to instruct cells to produce viral proteins to trigger an immune response.
Another type relies on "viral vectors" - harmless viruses that deliver genetic material into human cells to stimulate immunity. Both types of vaccines were gamechangers during the COVID pandemic.
Other technologies include nanoparticles , which use synthetic biological particles to improve delivery and immune response. And "virus-like particles", which trigger immune responses by imitating the structure of viruses , but don't contain any genetic material.
Researchers are also using powerful computational tools to design vaccines that could work across multiple strains.
These platforms aren't just being explored for flu and COVID - similar efforts are underway for other fast-evolving viruses, such as HIV .
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Earlier this month, the US government announced a US$500 million (£377 million) investment to accelerate research into universal vaccines. After years of underfunding, experts say this backing is long overdue - especially following the COVID pandemic, which temporarily shifted focus to emergency vaccine production.
The rapid development of COVID vaccines showed how targeted funding and global collaboration can lead to scientific breakthroughs. A similar approach could now help bring universal vaccines closer to reality by supporting early research, funding clinical trials and improving manufacturing and distribution systems.
However, the investment has not been without controversy. Some scientists have raised concerns that the funding may be overly directed toward a narrow set of researchers or outdated methods, rather than being open to the most promising technologies.
Critics argue that a broad, flexible portfolio of vaccine strategies - rather than a single approach - is the key to success.
Ultimately, the goal of a universal vaccine is not just scientific. It's also practical and global: reducing the burden on health systems, lowering costs and transforming how the world responds to future outbreaks.
Antony Black does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.
