DUBLIN (Reuters) - The Irish government expects to be able to begin to vaccinate vulnerable people against COVID-19 in first quarter or first half of 2021, Deputy Prime Minister Leo Varadkar said on Sunday. “I’m increasingly optimistic, as is government, that we will see a vaccine approved in the next couple of months and that in the first half or first quarter of next year it’ll be possible to start vaccinating those most at risk,” Varadkar told RTE radio.