Guardian: It is one of the most remarkable success stories of the pandemic: the unproven technology that delivered the Moderna and Pfizer/BioNTech vaccines in record time, helping to turn the tide on Covid-19.
The vaccines are based on mRNA, the molecule that instructs our cells to make specific proteins. By injecting synthetic mRNA, our cells are turned into on-demand vaccine factories, pumping out any protein we want our immune system to learn to recognise and destroy.
Pre-pandemic, the technology was viewed with scepticism – a clever concept, but not guaranteed to deliver. Now there is growing confidence that mRNA vaccines could have far-reaching applications in tackling diseases from flu to malaria.
Every February flu scientists take part in an annual ritual: bets are placed at a World Health Organization meeting on which flu strains will dominate the following winter. There are four influenza viruses in circulation, each rapidly evolving so that the previous year’s vaccines will have lost efficacy.
Manufacturers need at least six months to produce vaccines, a laborious process that involves growing attenuated virus inside millions of chicken eggs. When the flu forecast is on target, vaccines can be 60% effective, but a mismatch between vaccines and circulating strains can result in efficacy as low as 10%.
The holy grail of flu research is a universal vaccine that would work across all four strains…read more…