Children 5 and older now have a coronavirus vaccine. But many parents of younger kids are still anxiously waiting.

Sean O’Leary said the delta variant is so contagious that “pretty much any age group is at risk of getting it and spreading it, including kids under 5.” Parents must now also grapple with the omicron variant. Scientists are worried that mutations could make omicron more transmissible, but there is too little research so far to draw any conclusions.