A new public-health model projects that a sustained 10-percentage-point decline in Iowa childhood vaccination coverage could produce about 9,400 additional cases of vaccine-preventable disease over five years. The Iowa scenario also estimates 176 additional hospitalizations and $19.6 million in added health costs, according to reporting on the model’s state results.
The figures are not a forecast that Iowa will experience those outcomes. They are a modeled comparison between a hypothetical coverage decline and a baseline in which coverage does not fall. That distinction matters because the tool is designed to measure potential consequences under user-selected scenarios, not to predict the timing or location of an outbreak.
The expanded VaxImpactMap, developed by researchers affiliated with Emory University’s Rollins School of Public Health, now covers rotavirus, pertussis, invasive pneumococcal disease, chickenpox, invasive Haemophilus influenzae type b disease and respiratory syncytial virus among infants. Its methodology says disease-specific models are calibrated to national surveillance estimates and applied to states using their population and immunization-coverage data. It reports the additional cases, hospitalizations, deaths, missed workdays and costs associated with lower coverage.
Iowa’s result arrives as exemptions from school vaccination requirements are rising nationally. The Centers for Disease Control and Prevention reported that 4.2% of U.S. kindergartners had an exemption from at least one required vaccine in the 2025-26 school year, up from 3.6% a year earlier. Exemptions increased in 41 states and the District of Columbia, and 24 states reported rates above 5%.
In Iowa, the kindergarten exemption rate reached 4.9% in the latest year cited by the new analysis, more than double the 2.2% recorded in 2020-21. Iowa also removed the notarization requirement for religious exemption forms in 2024, and a later state law required schools and other covered educational institutions to include exemption information when communicating vaccination requirements to families. Those policy changes do not establish that coverage will fall by the 10 points used in the model, but they provide context for why state trends are being watched.
For families and schools, Iowa Health and Human Services maintains the state’s vaccination requirements, schedules and program resources. The model does not alter those rules or determine an individual child’s medical care. Its practical use is narrower: it gives state officials, health systems and legislators a common estimate of the health and budget exposure associated with different coverage levels.
The Iowa numbers should therefore be read as a planning benchmark. If coverage remains stable, the modeled additional burden would not materialize in the form presented. If it declines, the estimates give decision-makers a way to compare prevention efforts with the potential cost of additional disease and hospital care. The public methodology also lets officials test other coverage scenarios rather than treating one hypothetical decline as inevitable.
