OBJECTIVES: Cytomegalovirus (CMV) is a herpes virus that infects half of the United States (US) population by early adulthood. While mostly self-limiting in healthy individuals, primary CMV infection can occasionally cause symptomatic illness including infectious mononucleosis. We examined direct healthcare costs attributable to primary symptomatic (diagnosed) CMV in US claims data.

METHODS: This retrospective study utilized the Merative™ MarketScan® Commercial Claims and Encounters data during a pre-COVID-19 pandemic period (June 30, 2017 to February 29, 2020). Individuals aged 9-50 years with ≥1 primary or ≥2 secondary diagnoses for CMV (ICD-10: B25.x, B27.1x, P35.1) were selected for the CMV cohort (first diagnosis = index date). Controls (no CMV diagnosis at any point) were matched 1:1 on the date of a healthcare visit that was the same as the index date for the case (±7 days), as well as on demographics, region, insurance type, index year, Quan-Charlson comorbidity index, and immunocompromised status at baseline. Codes for solid organ, stem cell, or blood transplants at any point were an exclusion criterion. All individuals were required to have ≥6 months of continuous health plan enrollment pre-index (baseline) and post-index (follow-up). All-cause total direct costs (in 2022 USD) were summarized over a 6-month follow-up period.

RESULTS: 845 commercially insured matched pairs were included. Among CMV cases and non-CMV controls, the mean age at index date was 31 (standard deviation: ±11) years, 62% were female, and 13% were immunocompromised. Median total direct costs (medical and pharmacy) during the 6-month follow-up period were $4,689 (interquartile range: $1,377, $20,075) for CMV cases and $1,723 ($533, $7,228) for controls. Excess costs due to CMV were estimated at $2,966 (p<0.0001).

CONCLUSIONS: Individuals diagnosed with CMV had higher all-cause costs during the 6 months post-diagnosis than non-CMV controls. CMV prevention via vaccination may have a positive impact on these healthcare costs.