The quest for a universal coronavirus vaccine

As vaccine makers rush to stamp out new Covid-19 variants, some scientists have set their sights higher, aiming for a universal coronavirus vaccine that could tackle any future strains and possibly even stave off another pandemic. Since the race for a first Covid jab supercharged a new generation of vaccine technology, there have been numerous efforts to develop pan-coronavirus immunisation. Drew Weissman of the University of Pennsylvania, who was a pioneer of the mRNA technology used in Pfizer's Covid vaccine, is leading one such project. He said the problem with updating current vaccines to target all existing strains -- a plan announced by Pfizer earlier this month -- is that 'new variants are going to appear every three or six months'.