Scientists have taken a step forward in their quest to develop a vaccine for common colds by identifying a "promising target" on the virus which causes Covid-19. It is hoped that a "pan-coronavirus" vaccine would offer some protection against new variants of the virus which causes Covid, as well a common colds.
Such a vaccine could provide some resilience if new coronavirus diseases emerge. But developing this type of vaccine has proved difficult because there is a number of different coronaviruses, each with key differences which can mutate.
These mutations can reduce a person's immunity from the virus, which leaves them vulnerable to reinfection - which is why people repeatedly have common colds and some have been infected with multiple different variants of the virus which causes Covid-19 - Sars-CoV-2. And a vaccine which targets multiple coronaviruses would need to trigger antibodies in the body which recognise and "neutralise" a range of different coronavirus.
