Estimating the Burden of Vaccine-Preventable Infectious Diseases Caused by Herpesviruses Beyond Herpes Zoster in Europe: What's Going on in Spain and Germany?

OBJECTIVES: To analyse the in-hospital burden of vaccine-preventable diseases caused by herpesviruses with on-going clinical developments and no vaccination alternatives.

METHODS: Firstly, we reviewed ClinicalTrials.gov to identify herpesviruses that are experiencing growing clinical research for prevention and without available vaccines and selected the cytomegalovirus (CMV) and Epstein-Barr virus (EBV). We used publicly available aggregated retrospective real-world data of in-hospital diagnoses and length-of-stay (LoS) identified through ICD-10 codes from the Spanish National Hospital Discharge Database (RAE-CMBD) and the Institute for the Hospital Remuneration System (InEK) in Germany. Mean cost/patient was available in RAE-CMBD, but not in InEK, therefore we approximated it using the DRGs associated, their weights and the Bundesbasisfallwerte. Data was available for 2016-2021 for Spain and 2019-2022 in Germany.

RESULTS: In 2021, a total number of 2,931 hospitalized cases with a primary diagnostic of CMV (2,047) or EBV (884) was reported in Spain. While the LoS was higher for CMV (11.98/5.26 days) the mean cost/patient was similar (€3,443/€3,058). In the same year in Germany, the total number of CMV and EBV hospitalized cases was 7,280 (1,877/5,403) and the LoS was similar to Spain (12.2/4.3 days). The mean cost/patient was €3,195 for CMV and €1,593 for EBV. In 2021, CMV and EBV caused a total hospital spending of 9.8€M in Spain and 15.5€M in Germany. Both infections accumulated a substantial burden in adults between 16-59 years.

CONCLUSIONS: CMV and EBV caused a substantial burden on hospital resources in 2021 in at least two European countries presenting different healthcare provisioning models. An increasing trend in hospitalisations since 2016 was observed in Spain for both viruses, but more public pre- and post-pandemic data are needed to assess the trend in Germany. Increased surveillance and real-world data sharing has the potential to confirm the trends in this analysis and may inform effective resource allocation for prevention.