The potential economic value of a Staphylococcus aureus vaccine among hemodialysis patients.

Staphylococcus aureus infections are a substantial problem for hemodialysis patients. Several vaccine candidates are currently under development, with hemodialysis patients being one possible target population. To determine the potential economic value of an S. aureus vaccine among hemodialysis patients, we developed a Markov decision analytic computer simulation model. When S. aureus colonization prevalence was 1%, the incremental cost-effectiveness ratio (ICER) of vaccination was ≤$25,217/quality-adjusted life year (QALY). Vaccination became more cost-effective as colonization prevalence, vaccine efficacy, or vaccine protection duration increased or vaccine cost decreased. Even at 10% colonization prevalence, a 25% efficacious vaccine costing $100 prevented 29 infections, 21 infection-related hospitalizations, and 9 inpatient deaths per 1000 vaccinated HD patients. Our results suggest that an S. aureus vaccine would be cost-effective (i.e., ICERs ≤ $50,000/QALY) among hemodialysis patients over a wide range of S. aureus prevalence, vaccine costs and efficacies, and vaccine protection durations and delineate potential target parameters for such a vaccine.

The potential economic value of a 'universal' (multi-year) influenza vaccine.

BACKGROUND: Limitations of the current annual influenza vaccine have led to ongoing efforts to develop a 'universal' influenza vaccine, i.e., one that targets a ubiquitous portion of the influenza virus so that the coverage of a single vaccination can persist for multiple years. OBJECTIVES: To estimate the economic value of a 'universal' influenza vaccine compared to the standard annual influenza vaccine, starting vaccination in the pediatric population (2-18 year olds), over the course of their lifetime. PATIENT/METHODS: Monte Carlo decision analytic computer simulation model. RESULTS: Universal vaccine dominates (i.e., less costly and more effective) the annual vaccine when the universal vaccine cost ≤ $100/dose and efficacy ≥ 75% for both the 5- and 10-year duration. The universal vaccine is also dominant when efficacy is ≥ 50% and protects for 10 years. A $200 universal vaccine was only cost-effective when ≥ 75% efficacious for a 5-year duration when annual compliance was 25% and for a 10-year duration for all annual compliance rates. A universal vaccine is not cost-effective when it cost $200 and when its efficacy is ≤ 50%. The cost-effectiveness of the universal vaccine increases with the duration of protection. CONCLUSIONS: Although development of a universal vaccine requires surmounting scientific hurdles, our results delineate the circumstances under which such a vaccine would be a cost-effective alternative to the annual influenza vaccine.

Would school closure for the 2009 H1N1 influenza epidemic have been worth the cost?: a computational simulation of Pennsylvania.

BACKGROUND: During the 2009 H1N1 influenza epidemic, policy makers debated over whether, when, and how long to close schools. While closing schools could have reduced influenza transmission thereby preventing cases, deaths, and health care costs, it may also have incurred substantial costs from increased childcare needs and lost productivity by teachers and other school employees. METHODS: A combination of agent-based and Monte Carlo economic simulation modeling was used to determine the cost-benefit of closing schools (vs. not closing schools) for different durations (range: 1 to 8 weeks) and symptomatic case incidence triggers (range: 1 to 30) for the state of Pennsylvania during the 2009 H1N1 epidemic. Different scenarios varied the basic reproductive rate (R(0)) from 1.2, 1.6, to 2.0 and used case-hospitalization and case-fatality rates from the 2009 epidemic. Additional analyses determined the cost per influenza case averted of implementing school closure. RESULTS: For all scenarios explored, closing schools resulted in substantially higher net costs than not closing schools. For R(0) = 1.2, 1.6, and 2.0 epidemics, closing schools for 8 weeks would have resulted in median net costs of $21.0 billion (95% Range: $8.0 - $45.3 billion). The median cost per influenza case averted would have been $14,185 ($5,423 - $30,565) for R(0) = 1.2, $25,253 ($9,501 - $53,461) for R(0) = 1.6, and $23,483 ($8,870 - $50,926) for R(0) = 2.0. CONCLUSIONS: Our study suggests that closing schools during the 2009 H1N1 epidemic could have resulted in substantial costs to society as the potential costs of lost productivity and childcare could have far outweighed the cost savings in preventing influenza cases.

Economic model for emergency use authorization of intravenous peramivir.

OBJECTIVES: To develop 3 computer simulation models to determine the potential economic effect of using intravenous (IV) antiviral agents to treat hospitalized patients with influenza-like illness, as well as different testing and treatment strategies. STUDY DESIGN: Stochastic decision analytic computer simulation model. METHODS: During the 2009 influenza A(H1N1) pandemic, the Food and Drug Administration granted emergency use authorization of IV neuraminidase inhibitors for hospitalized patients with influenza, creating a need for rapid decision analyses to help guide use. We compared the economic value from the societal and third-party payer perspectives of the following 4 strategies for a patient hospitalized with influenza-like illness and unable to take oral antiviral agents: Strategy 1: Administration of IV antiviral agents without polymerase chain reaction influenza testing. Strategy 2: Initiation of IV antiviral treatment, followed by polymerase chain reaction testing to determine whether the treatment should be continued. Strategy 3: Performance of polymerase chain reaction testing, followed by initiation of IV antiviral treatment if the test results are positive. Strategy 4: Administration of no IV antiviral agents. Sensitivity analyses varied the probability of having influenza (baseline, 10%; range, 10%-30%), IV antiviral efficacy (baseline, oral oseltamivir phosphate; range, 25%-75%), IV antiviral daily cost (range, $20-$1000), IV antiviral reduction of illness duration (baseline, 1 day; range, 1-2 days), and ventilated vs nonventilated status of the patient. RESULTS: When the cost of IV antiviral agents was no more than $500 per day, the incremental cost-effectiveness ratio for most of the IV antiviral treatment strategies was less than $10,000 per quality-adjusted life-year compared with no treatment. When the cost was no more than $100 per day, all 3 IV antiviral strategies were even more cost-effective. The order of cost-effectiveness from most to least was strategies 3, 1, and 2. The findings were robust to changing risk of influenza, influenza mortality, IV antiviral efficacy, IV antiviral daily cost, IV antiviral reduction of illness duration, and ventilated vs nonventilated status of the patient for both societal and third-party payer perspectives. CONCLUSION: Our study supports the use of IV antiviral treatment for hospitalized patients with influenza-like illness.

Cost-effectiveness of adjuvanted versus nonadjuvanted influenza vaccine in adult hemodialysis patients.

BACKGROUND: Currently more than 340,000 individuals are receiving long-term hemodialysis (HD) therapy for end-stage renal disease and therefore are particularly vulnerable to influenza, prone to more severe influenza outcomes, and less likely to achieve seroprotection from standard influenza vaccines. Influenza vaccine adjuvants, chemical or biologic compounds added to a vaccine to boost the elicited immunologic response, may help overcome this problem. STUDY DESIGN: Economic stochastic decision analytic simulation model. SETTING & PARTICIPANTS: US adult HD population. MODEL, PERSPECTIVE, & TIMEFRAME: The model simulated the decision to use either an adjuvanted or nonadjuvanted vaccine, assumed the societal perspective, and represented a single influenza season, or 1 year. INTERVENTION: Adjuvanted influenza vaccine at different adjuvant costs and efficacies. Sensitivity analyses explored the impact of varying influenza clinical attack rate, influenza hospitalization rate, and influenza-related mortality. OUTCOMES: Incremental cost-effectiveness ratio of adjuvanted influenza vaccine (vs nonadjuvanted) with effectiveness measured in quality-adjusted life-years. RESULTS: Adjuvanted influenza vaccine would be cost-effective (incremental cost-effectiveness ratio <$50,000/quality-adjusted life-year) at a $1 adjuvant cost (on top of the standard vaccine cost) when adjuvant efficacy (in overcoming the difference between influenza vaccine response in HD patients and healthy adults) ≥60% and economically dominant (provides both cost savings and health benefits) when the $1 adjuvant's efficacy is 100%. A $2 adjuvant would be cost-effective if adjuvant efficacy was 100%. LIMITATIONS: All models are simplifications of real life and cannot capture all possible factors and outcomes. CONCLUSIONS: Adjuvanted influenza vaccine with adjuvant cost ≤$2 could be a cost-effective strategy in a standard influenza season depending on the potency of the adjuvant.

Forecasting the economic value of an Enterovirus 71 (EV71) vaccine.

Enterovirus 71 (EV71) is a growing public health concern, especially in Asia. A surge of EV71 cases in 2008 prompted authorities in China to go on national alert. While there is currently no treatment for EV71 infections, vaccines are under development. We developed a computer simulation model to determine the potential economic value of an EV71 vaccine for children (<5 years old) in China. Our results suggest that routine vaccination in China (EV71 infection incidence ≈0.04%) may be cost-effective when vaccine cost is $25 and efficacy ≥70% or cost is $10 and efficacy ≥50%. For populations with higher infection risk (≥0.4%), a $50 or $75 vaccine would be highly cost-effective even when vaccine efficacy is as low as 50%.

Economics of influenza vaccine administration timing for children.

OBJECTIVES: To determine how much should be invested each year to encourage and operationalize the administration of influenza vaccine to children before November and how late the vaccine should be offered each year. STUDY DESIGN: Monte Carlo decision analytic computer simulation models. METHODS: The children's influenza vaccination timing model quantified the incremental economic value of vaccinating a child earlier in the influenza season and the incremental cost of delaying vaccination. The children's monthly influenza vaccination decision model evaluated the cost-effectiveness of vaccinating versus not vaccinating for every month of the influenza season. RESULTS: Getting children vaccinated by the end of October rather than when they are currently getting vaccinated could save society between $6.4 million and $9.2 million plus 653 and 926 quality-adjusted life-years (QALYs) and third-party payers between $4.1 million and $6.1 million plus 647 to 942 QALYs each year. Decision makers may want to continue offering influenza vaccination to children at least through the end of December. Vaccinating with trivalent inactivated virus vaccine was more cost-effective than vaccinating with live attenuated influenza vaccine for every month. CONCLUSION: Policymakers could invest up to $6 million to $9 million a year to get children vaccinated in September or October without expending any net costs.

The timing of influenza vaccination for older adults (65 years and older).

While studies have found influenza vaccination to be cost-effective in older adults (65 years or older), they have not looked at how the vaccine's economic value may vary with the timing of vaccine administration. We developed a set of computer simulation models to evaluate the economic impact of vaccinating older adults at different months. Our models delineated the costs and utility losses in delaying vaccination past October and suggest that policy makers and payors may consider structuring incentives (< or =$2.50 per patient) to vaccinate in October. Our results also suggest that vaccination is still cost-effective through the end of February.