OBJECTIVES

The UK herpes zoster (HZ) national immunisation programme currently covers individuals aged 70-79 years-old. Research suggests a large proportion of ≥80 year-olds previously eligible may have missed out on vaccination, remaining at increased risk of disease. The study describes the disease burden of HZ and post-herpetic neuralgia (PHN) in the immunocompetent unvaccinated UK population aged ≥80 years. Additionally, the number of individuals who lost eligibility due to the 80-year cut-off in the UK vaccination programme has been estimated.

METHODS

Immunocompetent individuals unvaccinated against HZ and aged ≥80 years were identified using Clinical Practice Research Datalink (CPRD) / Hospital Episode Statistics (HES) data during the study period (1st September 2013 until 30^th June 2018). From this the HZ and PHN incidence rates were calculated per 1,000 person-years and stratified by age groups (80-84, 85-90 and ≥90 years). Additionally, the number of individuals who have lost eligibility for vaccination due to the age cut-off was calculated.

RESULTS

In the study 255,613 individuals contributed 580,326 person-years of follow-up. Overall HZ incidence in those ≥80 was 8.43/1,000 person-years and decreased with age from 8.85 in 80-84 year-olds to 7.37 in the ≥90 year-olds. Further investigations showed HZ rate was lowest in those aged ≥96 years (5.27/1,000 person-years). Overall PHN incidence was 0.80/1,000 person-years, and also decreased with age from 0.85 in the 80-84 cohort to 0.56 in those aged ≥90. Overall 16.8% of the study population had lost eligibility to the vaccination programme whilst 83.6% had never been eligible for the vaccine

CONCLUSIONS

The incidence and burden of HZ and PHN remains significant in the those ≥80 years old. However, interestingly that burden seems to decline in those ≥90. Nonetheless the importance of vaccination to the oldest individuals remains high and a significant number of people are missing out on the available protection.