Isabel Kershner

By Isabel Kershner An Israeli hospital on Monday began a study to test the safety and effectiveness of a fourth dose of a Covid-19 vaccine, as health officials continued to deliberate over rolling out fourth shots for vulnerable people nationwide. Officials...

Some scientists warn that too many shots might actually harm the body’s ability to fight the Covid-19 virus. But Israeli experts say there isn’t time to wait. By Isabel Kershner Israel is considering whether to approve a fourth Covid-19 vaccine dose for...