A study of more than 6 million children vaccinated against varicella found that the likelihood of these children to concurrently develop pediatric shingles, was reduced.
A new study assessing over 6 million children who received vaccination against the chickenpox virus — varicella — found that these individuals were also less likely to suffer from developing pediatric shingles.
Shingles — herpes zoster — results from contraction of the varicella–zoster virus. The Centers for Disease Control and Prevention (GA, USA) estimates that there are 1 million instances of herpes zoster in the United States each year. Pediatric herpes zoster, however, is very rare.
A new study, funded by the Center for Disease Control and Prevention, assessed the electronic health records of over 6.3 million children between 2003 and 2014, integrating data from 6 health care organizations. Approximately 50% of these children were vaccinated for some, or all, of this study period.
Sheila Weinmann, lead study investigator on behalf of Kaiser Permanente (CA, USA), explained that the study “…looked at the incidence rates of HZ overall, at how many cases there were per 100,000 person-years, including by age and gender.”
Person-years is a measurement that takes into account both the number of children in the study, and the amount of time each child spent in the study over its 12-year course.
Overall, herpes zoster risk was significantly lower amongst vaccinated individuals compared to unvaccinated children.
More specifically, over the 12-year course of the study, the rate of pediatric herpes zoster declined by 72%, as the number of vaccinated children increased.
Further, prevalence of herpes zoster was 78% lower amongst vaccinated children than unvaccinated, and, between five and six times lower compared to immunosuppressed children who were unable to receive vaccination.
Weinmann commented that the highest rates of herpes zoster were observed “…in the early years of the study when there was a higher proportion of children, particularly older children, who had not received the varicella vaccine.”
Increased vaccination rates over the 12-year study period notably reduced the contraction risk of herpes zoster for all children, even unvaccinated individuals.
The decline in herpes zoster risk could also be attributed to the introduction of the second vaccine dose, introduced in 2007.
Weinmann concluded that: “Since the introduction of the chickenpox vaccine, we have known how effective it is in preventing children from contracting that itchy and painful disease.” This study now demonstrates “…that the vaccine does reduce the likelihood of shingles in kids, highlighting the dual benefits of the chickenpox vaccine.”