From 2003 to 2014, there was a decrease in herpes zoster (HZ) incidence among children, with lower incidence rates for varicella-vaccinated versus unvaccinated children, according to a study published in Pediatrics.
Sheila Weinmann, Ph.D., from Kaiser Permanente Northwest in Portland, Oregon, and colleagues examined HZ incidence in children during a 12-year period from 2003 to 2014. The incidence rates of HZ were calculated per 100,000 person years of health plan membership for all children and among varicella-vaccinated versus unvaccinated children. Data were included for 6,372,067 children with at least one month of health plan membership.
The researchers found that the crude HZ incidence rate for all children was 74 per 100,000 person-years for the 12-year period. The rate was 78 percent lower for children who were vaccinated versus those who were unvaccinated (38 versus 170 per 100,000 person-years). From 2003 to 2014, there was a 72 percent decline in HZ incidence overall. Children who were vaccinated consistently had lower annual rates than those who were unvaccinated.
"Of concern are the children who may not be vaccinated in an era of vaccine hesitancy when clinical varicella is becoming uncommon," write the authors of an accompanying editorial. "Efforts to immunize all children against chickenpox must continue to be made to protect our population from wild-type varicella zoster virus."
Several authors disclosed financial ties to the pharmaceutical industry.
