In the second phase, people aged above 60 years and those over 45 with comorbidities will be vaccinated.
They both share a common mutation called N501Y, a slight alteration on one spot of the spike protein that coats the virus.
Northern Ireland went into a six-week lockdown and in Wales, restrictions that were relaxed for Christmas Day were also re-imposed.
According to the scientists, including those from Monash University in Australia, specific cells within the immune system called memory B cells, "remembers" infection...
Italy, where the continent's pandemic began, registered 484 COVID-19 deaths in one day, one of its lowest one-day death counts in about a month.