For children in the age group, 6 months through 4 years, parental apprehension has so far resulted in the administration of scarcely a trickle of Covid shots. Since June 18, when they became eligible, just 2.8 percent of those children had received shots, the foundation found recently in a separate analysis of federal vaccine data. By comparison, 18.5 percent of children ages 5 through 11, who have been eligible for Covid shots since October, had been vaccinated at a similar point in the rollout of their shots.

The new survey found that 43 percent of parents with children under 5 said they would “definitely not” have them vaccinated. About 27 percent said they would “wait and see,” while another 13 percent said they would have their children vaccinated “only if required.” Even some parents who were themselves vaccinated against Covid said they would not give permission for their youngest children.

The new analysis of parents’ views comes as vaccine uptake for older children has been slowing markedly. To date, only 40 percent of children 5 to 11 have been vaccinated. In the new survey, 37 percent of parents said they would “definitely not” get a Covid vaccine for their child in that age group.