We evaluated the economic impact of routine childhood immunization in the United States, reflecting updated vaccine recommendations and recent data on epidemiology and coverage rates.
An economic model followed the 2017 US birth cohort from birth through death; impact was modeled via a decision tree for each of the vaccines recommended for children by the Advisory Committee on Immunization Practices as of 2017 (with annual influenza vaccine considered in scenario analysis). Using information on historic prevaccine and vaccine-era incidence and disease costs, we calculated disease cases, deaths, disease-related healthcare costs, and productivity losses without and with vaccination, as well as vaccination program costs. We estimated cases and deaths averted because of vaccination, life-years and quality-adjusted life-years gained because of vaccination, incremental costs (2019 US dollars), and the overall benefit-cost ratio (BCR) of routine childhood immunization from the societal and healthcare payer perspectives.
Over the cohort’s lifetime, routine childhood immunization prevented over 17 million cases of disease and 31 000 deaths; 853 000 life years and 892 000 quality-adjusted life-years were gained. Estimated vaccination costs ($8.5 billion) were fully offset by the $63.6 billion disease-related averted costs. Routine childhood immunization was associated with $55.1 billion (BCR of 7.5) and $13.7 billion (BCR of 2.8) in averted costs from a societal and healthcare payer perspective, respectively.
In addition to preventing unnecessary morbidity and mortality, routine childhood immunization is cost-saving. Continued maintenance of high vaccination coverage is necessary to ensure sustained clinical and economic benefits of the vaccination program.
Prior analyses have demonstrated that US childhood immunization is cost-saving, in addition to preventing unnecessary morbidity and mortality. Updated estimates of the public health impact of this program are needed, given changes in disease epidemiology and evolving childhood vaccination recommendations.
For the 2017 birth cohort, routine childhood immunizations prevented >17 million disease cases and 31 000 deaths. Vaccination costs ($8.5 billion) were fully offset by averted disease-related costs ($63.6 billion), with a benefit-cost ratio of 7.5 from the societal perspective.
In 1995, the American Academy of Pediatrics and the US Advisory Committee on Immunization Practices (ACIP) first issued a unified pediatric vaccination schedule, targeting 9 vaccine-preventable diseases.1 Since 2017 and through 2021, the ACIP-recommended schedule for routine childhood immunization has targeted 14 vaccine-preventable diseases: diphtheria, invasive Haemophilus influenzae type b, hepatitis A, hepatitis B, influenza, measles, mumps, pertussis, invasive Streptococcus pneumoniae, polio, rotavirus, rubella, tetanus, and varicella.2
The epidemiologic and economic impacts of routine childhood immunization on reducing disease burden in the United States have been well documented.3–7 In the most recent evaluation, Zhou and colleagues7 found that for the 2009 US birth cohort, routine childhood immunization prevented approximately 42 000 early deaths and 20 million cases of disease over the cohort’s lifetime, resulting in a net savings of $68.8 billion (2009 US dollars [USD]) in societal costs and benefit-cost ratios (BCRs) of 3.0 and 10.1 for the healthcare payer and societal perspectives, respectively.7 However, this analysis did not include the 13-valent pneumococcal conjugate vaccine (PCV13) and included only limited information on the impact of rotavirus vaccination.
The objective of the current study was to estimate the impact of childhood immunization in the United States, considering only the vaccines that are routinely administered from birth to age 10 years, as delineated in the 2017 vaccination schedule (which was largely unchanged as of 2021). This excludes vaccines that are recommended only for high-risk conditions (eg, meningococcal ACWY for asplenics), those that are recommended based on shared clinical decision-making (eg, meningococcal B for adolescents), those recommended only in certain geographical areas (eg, dengue vaccine), and those with allowances for starting earlier (eg, human papillomavirus vaccine at age 9 years). We update previous estimates by including recent observational evidence of the epidemiologic impact of the 13-valent pneumococcal vaccine8–15 and rotavirus vaccination16,17 as well as a scenario analysis of annual influenza vaccination (including the cost for 2 doses of influenza vaccine at first vaccination).
Methods
Model Description
We developed a decision-tree model in Microsoft Excel (Microsoft Corporation; Redmond, Washington) to analyze the impact of vaccination on the 2017 US birth cohort (3 855 500 children)18 during its lifetime (Fig 1), focusing on 9 childhood vaccines routinely administered from birth to age 10 years: diphtheria, tetanus, and acellular pertussis (DTaP); hepatitis A (HepA); hepatitis B (HepB); Haemophilus influenzae type b (Hib); inactivated polio vaccine (IPV); measles, mumps, rubella (MMR); PCV13; rotavirus; and varicella.2 Since influenza vaccination is recommended for children and adults, vaccination impact cannot be attributed solely to the pediatric schedule. Additionally, both vaccination coverage and effectiveness vary year to year19,20 ; thus, annual influenza vaccine was included only in the scenario analyses. Vaccination of the 2017 cohort was assumed to follow the ACIP child immunization schedule, with coverage based on national estimates.21
For each disease, outcomes were calculated without and with vaccination for every month until 12 months, and then for every year thereafter. From birth to 100 years, we subtracted the number of individuals who died because of all-cause or disease-specific mortality from that period’s cohort and progressed the remaining individuals to the next period (month or, after 12 months, year). Age-specific all-cause mortality, disease incidence, treatment costs, and probability of different outcomes were used to parameterize the decision tree for each disease (see Supplemental Tables 5–25).
The model compared vaccination according to the recommended schedule against no vaccination. For each disease and for the vaccination and no-vaccination scenarios, we calculated the total number of cases of a given severity by multiplying the likelihood of different clinical outcomes by the total number of expected cases. Total disease-related costs were calculated by multiplying costs for a given clinical outcome by the number of clinical outcomes among the total number of disease cases and summing over the different clinical outcomes per disease (see Disease Costs and Quality of Life Impacts section). Surviving individuals who developed long-term complications for some diseases accumulated disability-related costs, which were discounted over their remaining lifetimes. Costs were inflated to 2019 USD using the healthcare component of the personal consumption expenditures index for treatment costs, the general component of the consumer price index for nonmedical costs such as transport costs,22 and the employment cost index for productivity costs.23 Costs and outcomes were calculated from the healthcare payer and societal perspectives and discounted using the standard annual discount rate of 3%.24
After calculating clinical outcomes for the vaccination and no-vaccination scenarios, we estimated the reductions in overall and age-specific cases of disease caused by vaccination. For the scenarios without and with immunization, treatment costs associated with disease cases were assumed to be based on current standard of care. Similarly, deaths caused by each disease were estimated in both scenarios, using the most recent mortality rates when available.
For each vaccination scenario, we reported the total disease-related cases, deaths, costs, life-years (LYs) and quality-adjusted life-years (QALYs). Then, we calculated averted cases by subtracting the number of cases with vaccination from the number of cases without vaccination. Similarly, we calculated LYs and QALYs gained by subtracting LYs and QALYs with vaccination from those obtained in the without vaccination scenario. We calculated the incremental cost-effectiveness ratio by dividing the net costs of the immunization program by incremental QALYs gained. The BCR was calculated by dividing the incremental disease-related cost-savings by the net costs of the immunization program.
Disease Incidence and Clinical Outcomes
We calculated cases before and after each vaccine was routinely recommended; these incidence estimates are described in a companion article.25 Prevaccine incidence estimates were calculated from disease surveillance data (National Notifiable Diseases Surveillance System and Active Bacterial Core surveillance reports) or obtained from the literature. Vaccine-era disease incidence estimates were calculated as average values over the most recent 5 years of available data or obtained from estimates of cases averted or event rate reductions. Incidence estimates in each era were adjusted for underreporting when applicable.
Vaccination Program Costs
We calculated the costs of the vaccination program, which included vaccine acquisition, administration, and adverse event costs. Vaccination coverage, which was obtained from the 2017 National Immunization Survey-Child21,26 and 2019 to 2020 state and local immunization program27 data, was used to estimate the number of individuals vaccinated and number of doses administered.
Public and private vaccine acquisition costs were taken from the 2019 Centers for Disease Control and Prevention’s Vaccine Price List for Children28 (Table 1). The model assumed that 53% of childhood vaccines were purchased at the public price, such as through the Vaccines for Children program, and that 47% were purchased at the private price.7 When multiple vaccines were available for the same disease (eg, HepA vaccines), vaccine acquisition costs per dose were estimated by averaging the price across brands, without accounting for market share of specific products. To account for combination vaccines, which typically have a small price premium, higher average vaccine acquisition costs were tested in sensitivity analyses. The vaccine wastage rate was assumed to be 5%.7 Federal excise taxes for the Vaccine Injury Compensation Program were not included in vaccine acquisition costs, as they are collected from vaccine manufacturers.29
Vaccine . | Age at Vaccination . | Coverage, %a . | Acquisition Cost per Dose, by Purchasing Sourceb . | |
---|---|---|---|---|
Public, USD . | Private, USD . | |||
DTaP | 2, 4, 6, 15 mo, 4 y | 94.9 fully vaccinated | 17.90 | 27.45 |
HepA | 12, 18 mo | 59.7 fully vaccinated | 19.44 | 32.31 |
HepB | Birth, 1, 6 mo | 91.4 fully vaccinated | 13.17 | 23.50 |
Hibc | 3 dose: 2, 4, 12 mo | 80.7 fully vaccinated | 13.09 | 26.23 |
4 dose: 2, 4, 6, 12 mo | 9.44 | 13.53 | ||
MMR | 12 mo, 4 y | 95.2 fully vaccinated | 21.05 | 75.04 |
PCV13 | 2, 4, 6, 12 mo | 82.4 fully vaccinated | 131.77 | 180.05 |
Polio (IPV) | 2, 4, 6 mo, 4 y | 92.7 fully vaccinated | 13.30 | 33.53 |
Rotavirusd | 2 dose: 2, 4 mo | 73.2 fully vaccinated | 92.85 | 117.45 |
3 dose: 2, 4, 6 mo | 70.49 | 82.89 | ||
Varicella | 12, 18 mo | 94.8 fully vaccinated | 98.24 | 129.30 |
Vaccine . | Age at Vaccination . | Coverage, %a . | Acquisition Cost per Dose, by Purchasing Sourceb . | |
---|---|---|---|---|
Public, USD . | Private, USD . | |||
DTaP | 2, 4, 6, 15 mo, 4 y | 94.9 fully vaccinated | 17.90 | 27.45 |
HepA | 12, 18 mo | 59.7 fully vaccinated | 19.44 | 32.31 |
HepB | Birth, 1, 6 mo | 91.4 fully vaccinated | 13.17 | 23.50 |
Hibc | 3 dose: 2, 4, 12 mo | 80.7 fully vaccinated | 13.09 | 26.23 |
4 dose: 2, 4, 6, 12 mo | 9.44 | 13.53 | ||
MMR | 12 mo, 4 y | 95.2 fully vaccinated | 21.05 | 75.04 |
PCV13 | 2, 4, 6, 12 mo | 82.4 fully vaccinated | 131.77 | 180.05 |
Polio (IPV) | 2, 4, 6 mo, 4 y | 92.7 fully vaccinated | 13.30 | 33.53 |
Rotavirusd | 2 dose: 2, 4 mo | 73.2 fully vaccinated | 92.85 | 117.45 |
3 dose: 2, 4, 6 mo | 70.49 | 82.89 | ||
Varicella | 12, 18 mo | 94.8 fully vaccinated | 98.24 | 129.30 |
DTaP, MMR, and varicella vaccination coverage for kindergarten-aged children in 2019 to 2020 were obtained from Seither and McGill.27 All other coverage estimates were obtained from CDC data for 2017.21
All vaccine acquisition costs were obtained from the CDC vaccine price list as of March 2019.
A 50% market share for Hib vaccines was assumed for the 3-dose and 4-dose series.
Market shares for rotavirus vaccines were assumed to be 20% and 80% for the 2-dose and 3-dose series, respectively.70
For vaccine administration costs, we assumed that 80% of vaccines were administered by private providers and that the remaining 20% of vaccines were administered in public clinics.7 Unit costs of administration were obtained from the Centers for Medicare and Medicaid Services’ Physician Fee Schedule30 for privately administered vaccines, with the administration cost per dose dependent on the number of disease components included in each vaccine. For example, for the DTaP vaccine, which protects against 3 diseases, administration costs were equal to the costs associated with reimbursement for the initial disease component plus each of the 2 other disease components. Vaccines administered in a public setting incurred an administration cost of $8.40 per dose (2019 USD).7
We estimated the productivity loss costs associated with vaccination by multiplying 2 hours of lost caregiver time for each vaccination visit7 by the hourly cost of caregiver time of $21.24.31 Additionally, caregiver travel costs for each visit ($25.74) were applied.7 For vaccines typically administered during routine well-child visits, and in the presence of a wide variation in indirect costs associated with pediatric vaccination, we assumed that 50% of caregiver time and travel costs were attributed to vaccination.7,32–40
Vaccinated individuals were assumed to experience adverse events and associated direct medical costs and disutilities (Supplemental Tables 5 and 6). Incidence, cost, and disutility estimates for vaccine-related adverse events were obtained from previous economic analyses6,7,32,33,35,36,41–43 and validated with clinical expert opinion; events that were not considered causally attributable to vaccination by the Institute of Medicine were excluded.44–53
Disease Costs and Quality-of-Life Impacts
To capture the costs and impact of infectious diseases on quality of life, we used disease-specific severity distributions to calculate the number of clinical outcomes for each disease. The direct medical cost, disutility value, and duration of disease per clinical outcome were based on the published literature (Supplemental Table 21).
Productivity loss costs were calculated using the human capital approach.6,7,54,55 Specifically, disease-related productivity costs were calculated as the number of cases at each age multiplied by mean workdays lost divided by 365, which was then multiplied by the age-specific market and nonmarket annual productivity31 (Supplemental Tables 22 and 24). For disease cases resulting in long-term sequelae, the model assumed the percentage reduction in annual productivity was equal to the percentage reduction in health-related utility weights associated with the complication (Supplemental Table 23). Average age-specific estimates of annual productivity and life expectancy were used to calculate the discounted present value of lifetime productivity loss costs associated with disease-related mortality and long-term sequelae (Supplemental Tables 24 and 25).31,56,57
Analyses
In addition to base-case analyses, we conducted additional univariate scenario analyses to assess the robustness of health and economic outcomes to changes in key analysis assumptions. Scenarios considered variations to assumptions for the following: (1) 100% increase in vaccine administration costs, (2–3) 10% increase and reduction in the percentage of vaccines publicly purchased, (4) 5% increase in vaccine acquisition costs, (5) 100% of indirect costs for caregiver time and travel for vaccination at well-child visits attributable to vaccination, (6) 0% annual discount rates, (7) 10% reduction in prevaccine disease incidence, (8) 50% increase in vaccine-era disease incidence, (9–10) 20% increase and decrease in healthcare payer disease-related costs, and (11) 20% reduction in case-fatality rates for modeled diseases. Another scenario (12) was conducted to include annual influenza vaccination and disease for children aged 0 to 10 years in the economic analysis. Annual influenza vaccination coverage was based on coverage from the 2017 to 2018 season (67.8% and 59.5% for ages <5 years and 5–10 years, respectively).58 All children vaccinated received 2 doses at the time of their first influenza vaccination, per the ACIP-recommended schedule. Vaccine acquisition costs for influenza vaccines were obtained from the 2019 vaccines price list,28 and an average cost across products was calculated ($14.24 and $18.73 for public and private purchasing sources, respectively). Details for disease-related inputs are presented in Supplemental Table 11.
An additional scenario (13) included the value of QALYs saved in the societal BCR calculation.59 The value of QALYs saved was included in the benefits of vaccination by multiplying the number of QALYs saved by a willingness-to-pay threshold of $100 000 per QALY gained.60 Finally, a worst-case scenario (14) was presented by combining all input variations that negatively impacted the BCR, which included scenarios 1, 3, 4, 5, 7, 8, 10, and 11.
Results
Health Outcomes Without and With Vaccination
Over the lifetime of the 2017 US birth cohort, 21.2 million preventable disease cases were estimated without routine childhood immunization, resulting in 33 000 disease-related deaths, 876 500 LYs lost, and 931 400 QALYs lost. When vaccine-preventable diseases were modeled with routine childhood immunization, 3.4 million cases and 1600 disease-related deaths occurred, with 23 400 LYs and 39 800 QALYs lost. As a result, routine childhood immunization was associated with 17.8 million disease cases averted, 31 400 disease-related deaths averted, and an incremental gain of 853 000 LYs and 891 600 QALYs (Table 2). Incremental results varied by disease, with the most cases averted for pneumococcal disease, measles, and varicella and the most deaths averted for pneumococcal disease, diphtheria, and measles. Gains in LYs and QALYs were largest for diphtheria, pneumococcal disease, and measles (Table 2).
Disease . | Cases Averted (Thousands) . | Deaths Averted . | LYs Gained (Thousands) . | QALYs Gained (Thousands) . |
---|---|---|---|---|
Diphtheria | 219 | 21 870 | 655 | 580 |
Tetanus | <1 | 70 | 2 | 2 |
Pertussis | 1693 | 700 | 21 | 43 |
Hepatitis A | 21 | <10 | <1 | <1 |
Hepatitis B | 40 | 220 | 4 | 13 |
Haemophilus influenzae type b | 17 | 650 | 20 | 34 |
Measles | 2915 | 2330 | 70 | 83 |
Mumps | 1694 | <10 | <1 | 8 |
Rubella | 1371 | 20 | <1 | 7 |
Streptococcus pneumoniaea | 5851 | 5230 | 72 | 95 |
Polio | 25 | 240 | 6 | 8 |
Rotavirusb | 1280 | 20 | <1 | 4 |
Varicella | 2641 | 50 | 1 | 16 |
Total | 17 769 | 31 412 | 853 | 894c |
Total (Undiscounted) | 21 900 | 74 240 | 2787 | 2650c |
Disease . | Cases Averted (Thousands) . | Deaths Averted . | LYs Gained (Thousands) . | QALYs Gained (Thousands) . |
---|---|---|---|---|
Diphtheria | 219 | 21 870 | 655 | 580 |
Tetanus | <1 | 70 | 2 | 2 |
Pertussis | 1693 | 700 | 21 | 43 |
Hepatitis A | 21 | <10 | <1 | <1 |
Hepatitis B | 40 | 220 | 4 | 13 |
Haemophilus influenzae type b | 17 | 650 | 20 | 34 |
Measles | 2915 | 2330 | 70 | 83 |
Mumps | 1694 | <10 | <1 | 8 |
Rubella | 1371 | 20 | <1 | 7 |
Streptococcus pneumoniaea | 5851 | 5230 | 72 | 95 |
Polio | 25 | 240 | 6 | 8 |
Rotavirusb | 1280 | 20 | <1 | 4 |
Varicella | 2641 | 50 | 1 | 16 |
Total | 17 769 | 31 412 | 853 | 894c |
Total (Undiscounted) | 21 900 | 74 240 | 2787 | 2650c |
All health outcomes were discounted at an annual rate of 3%.
Streptococcus pneumoniae cases are defined as the sum of cases of invasive pneumococcal disease, Streptococcus pneumoniae pneumonia, and Streptococcus pneumoniae acute otitis media.
Rotavirus cases are defined as a sum of rotavirus-related hospitalizations, emergency department visits, outpatient visits, and nonmedically attended cases. The sum of these cases may be an overestimate of total rotavirus cases in the population, as some events may have multiple rotavirus-related visits.
Total discounted QALYs gained from cases of disease averted is ∼894 000; when accounting for incremental QALYs from vaccine-related adverse events, total QALYs gained is ∼892 000. Similarly, total undiscounted QALYs gained from cases of disease averted is ∼2 650 000, whereas total QALYs gained are ∼2 648 000 when adjusting for incremental QALYs from vaccine-related adverse events.
Undiscounted outcomes are shown in Table 2. For each disease evaluated, inclusion of the associated vaccine in the routine childhood immunization program reduced the number of cases; reductions ranged from approximately 47% for rotavirus cases to 100% for polio cases. More than 90% reduction in cases was achieved for 10 of the 13 diseases evaluated.
Economic Outcomes Without and With Vaccination
Lifetime societal disease-related costs for the 2017 birth cohort were $66.8 billion without childhood immunization, which included $22.4 billion in healthcare payer costs to treat cases of disease, $8.4 billion in productivity losses caused by cases of disease and long-term sequelae, and $36.0 billion in productivity losses caused by disease-related mortality (Fig 2). With routine childhood immunization, lifetime societal disease-related costs were $3.2 billion, including $1.3 billion in healthcare payer costs to treat cases of disease, $0.9 billion in productivity losses caused by cases of disease and long-term sequelae, and $1.0 billion in productivity losses caused by disease-related mortality.
Thus, societal disease-related cost-savings totaled $63.6 billion, with the highest savings being caused by averted cases of diphtheria, measles, and pneumococcal disease (Fig 3). For disease-related costs averted, direct medical costs to treat acute cases and long-term sequelae accounted for 33% of the savings, whereas the remaining costs averted were from productivity losses caused by cases and long-term sequelae (12%) and productivity loss caused by mortality (55%) (Table 3).
Incremental Outcome . | Healthcare Payer Perspective (Millions USD) . | Societal Perspective (Millions USD) . |
---|---|---|
Vaccination costs | ||
Acquisition | 5298 | 5298 |
Administration | 1941 | 1941 |
Adverse events | 175 | 175 |
Time and travel for vaccination | — | 1084 |
Disease-related costs | ||
Disease treatment | −21 067 | −21 067 |
Productivity loss caused by disease | — | −7555 |
Productivity loss caused by disease-related mortality | — | −34 950 |
Total incremental costs | −13 652 | −55 072 |
Benefit-cost ratio | 2.8 | 7.5 |
Incremental cost per QALY gained | Cost-saving | Cost-saving |
Value of QALYs saveda | — | 89 329 |
Incremental Outcome . | Healthcare Payer Perspective (Millions USD) . | Societal Perspective (Millions USD) . |
---|---|---|
Vaccination costs | ||
Acquisition | 5298 | 5298 |
Administration | 1941 | 1941 |
Adverse events | 175 | 175 |
Time and travel for vaccination | — | 1084 |
Disease-related costs | ||
Disease treatment | −21 067 | −21 067 |
Productivity loss caused by disease | — | −7555 |
Productivity loss caused by disease-related mortality | — | −34 950 |
Total incremental costs | −13 652 | −55 072 |
Benefit-cost ratio | 2.8 | 7.5 |
Incremental cost per QALY gained | Cost-saving | Cost-saving |
Value of QALYs saveda | — | 89 329 |
Data presented in US dollars unless otherwise indicated. —, not applicable.
The societal costs of the US routine vaccination program were $8.5 billion for the 2017 birth cohort. Most societal vaccination costs were from vaccine acquisition (62%), administration (23%), and caregiver time and travel (13%); adverse events constituted a small proportion of costs (2%). As a result of the disease-related costs averted, the US childhood immunization program was associated with a net savings of $55.1 billion and a BCR of 7.5 from the societal perspective. This BCR indicates that every dollar invested in the childhood immunization program is expected to result in $7.50 in savings to society. A BCR of 2.8 was observed from the healthcare payer perspective. Incremental costs per LY and per QALY saved were not applicable because the immunization program was cost-saving. However, using a willingness-to-pay threshold of $100 000 per QALY saved,60 the value of total QALYs saved by the childhood immunization program was approximately $89.2 billion.
Scenario Analyses
BCRs were most impacted by variations of annual discount rates, vaccine administration costs, and direct medical costs of disease cases (Table 4). Healthcare payer and societal BCRs were minimally impacted when assumptions impacting vaccine acquisition costs were varied. The economic value of routine childhood immunization was lower when annual influenza vaccination for children aged 0 to 10 years was included in the economic analysis, with healthcare payer and societal BCRs of 2.6 and 5.8 (compared with 2.8 and 7.5 in the base case), respectively. The societal BCR substantially increased when the value of QALYs saved was included in the BCR calculation (BCR = 18.0). When the scenarios negatively impacting the BCR of childhood immunization were simultaneously observed (ie, worst-case scenario), the healthcare payer and societal BCRs were 1.5 and 3.8, respectively.
Scenario . | Healthcare Payer BCR . | Societal BCR . |
---|---|---|
Base case | 2.8 | 7.5 |
Scenario 1: 100% increase in vaccine administration costs | 2.3 | 6.1 |
Scenario 2: 10% increase in public purchase of vaccines | 2.9 | 7.7 |
Scenario 3: 10% reduction in public purchase of vaccines | 2.8 | 7.3 |
Scenario 4: 5% increase in vaccine acquisition costs | 2.7 | 7.3 |
Scenario 5: 100% of indirect costs for caregiver time and travel for vaccinations at well-child visits attributable to vaccinationa | 2.8 | 6.6 |
Scenario 6: 0% annual discount rates | 5.3 | 21.0 |
Scenario 7: 10% reduction in pre-vaccine disease incidence | 2.5 | 6.7 |
Scenario 8: 50% increase in vaccine-era disease incidence | 2.8 | 7.3 |
Scenario 9: 20% increase in healthcare payer disease-related costs | 3.4 | 8.0 |
Scenario 10: 20% reduction in healthcare payer disease-related costs | 2.3 | 7.0 |
Scenario 11: 20% reduction in disease case-fatality rates | 2.8 | 6.7 |
Scenario 12: annual influenza vaccination and disease included in economic analysis | 2.6 | 5.8 |
Scenario 13: inclusion of value of QALYs saved in societal BCR | 2.8 | 18.0 |
Scenario 14: worst-case scenariob | 1.5 | 3.8 |
Scenario . | Healthcare Payer BCR . | Societal BCR . |
---|---|---|
Base case | 2.8 | 7.5 |
Scenario 1: 100% increase in vaccine administration costs | 2.3 | 6.1 |
Scenario 2: 10% increase in public purchase of vaccines | 2.9 | 7.7 |
Scenario 3: 10% reduction in public purchase of vaccines | 2.8 | 7.3 |
Scenario 4: 5% increase in vaccine acquisition costs | 2.7 | 7.3 |
Scenario 5: 100% of indirect costs for caregiver time and travel for vaccinations at well-child visits attributable to vaccinationa | 2.8 | 6.6 |
Scenario 6: 0% annual discount rates | 5.3 | 21.0 |
Scenario 7: 10% reduction in pre-vaccine disease incidence | 2.5 | 6.7 |
Scenario 8: 50% increase in vaccine-era disease incidence | 2.8 | 7.3 |
Scenario 9: 20% increase in healthcare payer disease-related costs | 3.4 | 8.0 |
Scenario 10: 20% reduction in healthcare payer disease-related costs | 2.3 | 7.0 |
Scenario 11: 20% reduction in disease case-fatality rates | 2.8 | 6.7 |
Scenario 12: annual influenza vaccination and disease included in economic analysis | 2.6 | 5.8 |
Scenario 13: inclusion of value of QALYs saved in societal BCR | 2.8 | 18.0 |
Scenario 14: worst-case scenariob | 1.5 | 3.8 |
A total of 50% of indirect costs for caregiver time and travel for vaccinations at well-child visits were assumed to be attributable to vaccination in the base-case analysis.
The worst-case scenario combined the input variations observed in Scenarios 1, 3, 4, 5, 7, 8, 10, and 11.
Discussion
We estimated that routine childhood immunization averted 17.8 million cases and 31 400 disease-related deaths for the 2017 US birth cohort over its lifetime, resulting in a net savings of $55.1 billion (BCR of 7.5) and $13.7 billion (BCR of 2.8) from a societal and healthcare payer perspective, respectively. Results were robust to variations in key input values. These estimates could be used to aid US national vaccination goals for increasing public awareness of the individual and societal benefits of the childhood immunization program,61,62 which are particularly important given recent decreases in childhood vaccination rates observed in the United States during the COVID-19 pandemic.63
Previous analyses have evaluated the economic impact of prior US pediatric vaccination schedules.6,7 From the healthcare perspective, the current BCR was similar to results previously obtained (2.8 versus 3.0 from Zhou and colleagues7 ); from a societal perspective, however, the estimated BCR was lower (7.5 versus 10.1 from Zhou and colleagues7 ). The difference in the societal BCR could be explained by the current model’s higher lost productivity caused by vaccination-related caregiver time and transport costs; we also calculated lower reductions in lifetime productivity losses from long-term complications and death.
Our analysis is useful for health economists, policy makers, and other stakeholders interested in ascertaining the benefits and observed impacts of childhood vaccination. Additional analyses should evaluate the impact of childhood vaccination among racial and ethnic groups that may be at increased risk for vaccine-preventable disease or that may have lower vaccination rates. Our analyses could not explore the impact of childhood vaccination within specific population strata because data on differences among racial and ethnic groups in vaccine coverage and disease incidence estimates are scarce and/or based on small population size. Further, continued changes to the ACIP vaccination schedule over time and the epidemiologic impacts of changes to vaccination patterns justify periodic economic evaluations of the childhood vaccination program. Future updates to these evaluations are of particular importance after a shock or disruption to a vaccination program, such as the COVID-19 pandemic, which may impact both disease incidence and population-level vaccination rates.
Some limitations of this analysis must be considered. Our model followed a birth cohort over its lifetime but modeled only pediatric vaccines and did not include the impact or cost of adolescent, adult, maternal, or booster vaccines relevant to our analysis (eg, influenza, TDaP booster, pneumococcal vaccines); this may overestimate the value of childhood immunization. However, our model did not capture the reduced incidence and associated cost-savings of diseases avoided for age groups outside the birth cohort through herd immunity. This was a conservative approach, thus underestimating the value of childhood immunization. Similarly, for the scenario including annual influenza vaccination, influenza incidence and vaccination were modeled only in children aged 0 to 10 years and therefore only captured direct protection of the influenza vaccine.
Prevaccine incidence estimates, for some diseases, corresponded to different historic periods, with possible differences in contact patterns affecting transmission. Vaccine-era incidence estimates use an average across multiple years, thus capturing but not accurately reflecting seasonal fluctuations or periodic outbreaks in a given year. This analytic framework also limits the analysis results to the time periods compared, and as such, our analysis does not account for potential changes in disease incidence over time. In addition, estimates of case-fatality ratios and disease management costs in the vaccine era could not be obtained for diseases that are nearly or fully eradicated. Of note, our sensitivity analyses showed that cost-savings from the childhood vaccination program were robust to variations in assumptions across these parameters.
In addition, each disease was modeled separately and did not allow for interaction across the diseases. For example, disease-related deaths for diphtheria did not reduce the size of the cohort modeled for tetanus. However, during prevaccine periods, children were exposed to multiple infectious disease risks and could die of multiple causes. Thus, the model expresses the value of reducing infectious disease morbidity and mortality across a variety of diseases. Additionally, this analysis did not capture all extended benefits of vaccination, such as increased educational attainment and productivity, reduced household financial risk, and reduced use of antimicrobial agents because of the averted cases of diseases that would have warranted such treatment.64–66 Furthermore, some aspects of vaccination impact are difficult to capture in models and may lead to underestimation of vaccination benefits. For example, natural measles infections may negatively affect immunologic memory for other pathogens67–69 ; this phenomenon is not observed in individuals with vaccine-induced immunity.68 Thus, our results serve as a conservative estimate of the value of the childhood immunization program.
Conclusions
From the healthcare payer and societal perspectives, the US childhood immunization program results in cost-savings caused by reductions in cases of disease and disease-related costs. This highlights the continued value of routine childhood immunization in reducing the clinical and economic burden of vaccine-preventable disease. Sustaining high levels of vaccination coverage and adherence to the recommended vaccination schedule are necessary to continue observing the benefits of the vaccination program.
Acknowledgments
Thank you to Kate Lothman of RTI Health Solutions, who provided medical writing support for the development of this manuscript and whose services were funded by Merck Sharp and Dohme LLC, a subsidiary of Merck and Co., Inc., Rahway, NJ.
Mr Carrico, Ms Talbird, Ms Mellott, and Dr La conceptualized and designed the study, reviewed the literature and derived the model parameters, interpreted the results, drafted the initial manuscript, and/or reviewed and revised the manuscript; Dr Chen, Dr Nyaku, Dr Carias, and Dr Roberts conceptualized the study and provided input on the study design, secured funding, interpreted the results, and reviewed and revised the manuscript; Dr Marshall provided input on the model parameters, interpreted the results, and reviewed and revised the manuscript; and all authors approved the final manuscript as submitted and agree to be accountable for all aspects of the work.
Dr La’s affiliation is GSK, Philadelphia, Pennsylvania.
FUNDING: This study was funded by Merck Sharp and Dohme LLC, a subsidiary of Merck & Co., Inc., Rahway, NJ.
CONFLICT OF INTEREST DISCLOSURES: Mr Carrico, Ms Talbird, and Ms Mellott are employed by RTI Health Solutions, which received funding for the conduct of this study. Dr La was an employee of RTI Health Solutions when this study was conducted and is now an employee and shareholder in the GSK group of companies. Dr Chen, Dr Carias, and Dr Roberts are employees of Merck Sharp and Dohme LLC, a subsidiary of Merck and Co., Inc., Rahway, NJ, USA, and are shareholders in Merck and Co., Inc., Rahway, NJ, USA. Dr Nyaku was an employee of Merck Sharp and Dohme LLC, a subsidiary of Merck and Co., Inc., Rahway, NJ, USA, and a shareholder in Merck and Co., Inc., Rahway, NJ, USA, when this study was conducted. Dr Marshall has been an investigator on clinical trials funded by GlaxoSmithKline, Merck, Pfizer, Sanofi Pasteur, and Seqirus, and he has received honoraria from these companies for service on advisory boards and/or nonbranded presentations.
COMPANION PAPERS: Companions to this article can be found online at http://www.pediatrics.org/cgi/doi/10.1542/peds.2021-056013 and http://www.pediatrics.org/cgi/doi/10.1542/peds.2022-057831.
- ACIP
Advisory Committee on Immunization Practices
- BCR
benefit-cost ratio
- DTaP
diphtheria, tetanus, and acellular pertussis vaccine
- HepA
hepatitis A vaccine
- HepB
hepatitis B vaccine
- Hib
Haemophilus influenzae type b vaccine
- IPV
inactivated polio vaccine
- LY
life-year
- MMR
measles, mumps, rubella vaccine
- PCV13
13-valent pneumococcal conjugate vaccine
- QALY
quality-adjusted life-year
- USD
United States dollars
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