BACKGROUND: Cytomegalovirus (CMV) is a common pathogen which establishes lifelong latency following primary infection. A pregnant woman can transmit CMV to her fetus, resulting in congenital CMV (cCMV). cCMV is the major infectious cause of sensorineural hearing loss (SNHL) in infants born in high-income countries. This analysis modelled the epidemiologic and cost impact of vaccinating women of child-bearing age in the US with a prophylactic vaccine to protect against CMV infection.
METHOD: A Markov model estimated the impact of potential vaccination strategies in preventing CMV, cCMV, and cCMV-related SNHL. For the base-case analysis, a cohort of US females aged 16-40 years were vaccinated with a hypothetical CMV vaccine. Model inputs were informed by a targeted literature search. Symptomatic CMV cases and all cCMV cases incurred direct costs (in USD). Additional targeted vaccination scenarios were also modelled, including vaccinating 16-to-40-year-old females pre- and post-first pregnancy.
RESULTS: The base-case vaccination strategy in 54,984,387 US females avoided 2,213,266 (95% CrI: 1,275,544-3,327,246) CMV cases, 45,600 (95% CrI: 27,815-66,725) cCMV cases, and 6,272 (95% CrI: 69-23,204) cCMV-associated SNHL cases (see Table 1). Direct costs due to CMV and cCMV decreased by a total of $10.4 billion (95% CrI: $5.5 billion-$17.0 billion). All targeted vaccination scenarios also resulted in case and cost reductions. Sensitivity analysis showed that key model drivers were natural history of infection and vaccine efficacy/durability.
CONCLUSIONS/LEARNING POINTS: This analysis demonstrated that, even without considering the potential horizontal transmission effects of vaccination, an effective CMV vaccine for females aged 16-40 years would result in a substantial public health benefit in the US with CMV, cCMV, and cCMV-related SNHL cases avoided and associated cost reductions. Several model parameters were based on assumptions and further evidence generation is needed.
