More parents are leery about vaccinating their children, even against once-common diseases like measles and whooping cough. New research suggests their beliefs are contagious too.
A groundbreaking study of 154,424 children covered by Kaiser Permanente in Northern California found five geographic clusters where children were significantly more likely to be underimmunized by their third birthday, including almost one in four toddlers in part of Vallejo, a city in the San Francisco Bay area. The approach may help doctors identify communities where parents are the most concerned and the chance of an outbreak is highest, the researchers said.
The findings published in Pediatrics confirm long-held speculation that opposition to immunizations can concentrate in communities, increasing the risk of outbreaks, said lead author Tracy Lieu, a pediatrician and director of the Kaiser Permanente Division of Research. They also bolster earlier findings that the number of children who aren’t getting the recommended vaccines, or receiving them on time, is on the rise.
“While complete refusal of all vaccines is quite rare, we know parental concern about vaccination has increased in the past decade,” she said. “We need to learn a lot more about what are the effective ways of communicating with parents.”