Israel is ramping up its campaign to give people a fourth vaccination against the coronavirus, after the Health Ministry announced that the jab would be made available to more groups. People at risk of becoming seriously ill with Covid-19, as well as their caregivers, are eligible, as are adults who are at particular risk of infection at their place of work, the ministry said late on Wednesday. The expansion of the nation’s fourth jab campaign follows a decision by Nachman Ash, the ministry’s director general. In order to get a fourth shot, the third must have taken place at least four months …