WASHINGTON: US federal health agencies on Tuesday recommended pausing the use of Johnson & Johnson’s Covi-19 vaccine after six women under 50 given the shot developed rare blood clots, dealing a fresh setback to efforts to tackle the pandemic. Following the news, Johnson & Johnson (J&J) said it was delaying the rollout of the vaccine to Europe, a week after regulators there said they were reviewing rare blood clots in four recipients of the shot in the United States. The moves come after European regulators said earlier this month they had found a possible link between AstraZeneca’s Covid-19 vaccine and a similar rare blood clotting problem that led to a small number of deaths.