In the United States and Canada, pediatric patients who undergo liver transplant show lower age-appropriate immunization rates at time of transplant than nontransplant recipients in a similar age group, according to a study published in JAMA.

Barely half of transplant recipients were up to date on the National Immunization Survey (NIS) seven-vaccine series compared with 70% of healthy children aged 19 to 35 months, researchers found.