Vaccines for the 21st Century: A Tool for Decisionmaking (2000)
Chapter: Appendix 6: Epstein-Barr Virus
APPENDIX 6
Epstein-Barr Virus
DISEASE BURDEN
Epidemiology
For the purposes of the calculations in this report, the committee estimated that there are 118,546 new infections with Epstein-Barr virus (EBV) each year in the United States. The infection occurs primarily in teenagers and young adults. 80% of the cases were estimated to occur in people between the ages of 15 and 24 years of age. It was assumed that males and females are affected equally. The committee assigned a case fatality rate of 0 to this infection.
Disease Scenarios
For the purposes of the calculation in this report, the committee estimated that 95% of infections manifest as uncomplicated mononucleosis (fever, lymphadenopathy, and pharyngitis). This state lasts three weeks and is associated with a health utility index (HUI) of .94. Approximately 5% of infections manifest in a more complicated manner (e.g. hepatitis). This state lasts 8 weeks and is associated with a much lower HUI, .47. Table A6–1 illustrates the estimated number of cases in each health state, the duration of time that state is experienced, and the health utility index (HUI) associated with each state.
See Appendix 28 for more information.
Table A6–1 Health Care Costs Associated with EBV Infection
| % of Cases | Duration (years) | Committee HUI Values | % with Care | Units per Case (or per year) | Form of Treatment |
Uncomplicated infectious mononucleosis | 95% |
| ||||
Fever, lymphadenopathy, pharyngitis |
| 0.0575 | 0.94 | 100% | 1.0 | Physician A |
Complicated infectious mononucleosis | 5% |
| 100% | 1.0 | Diagnostic A | |
e.g., hepatitis |
|
| 0.47 | 50% | 1.0 | Medication B |
|
| 0.1534 |
| 100% | 2.0 | Physician B |
| 100% | 1.0 | Diagnostic B | |||
50% | 1.0 | Medication B | ||||
|
COST INCURRED BY DISEASE
Table A6–1 summarizes the health care costs incurred by EBV infections. For the purposes of the calculations in this report, it was assumed that patients with uncomplicated mononucleosis incur costs associated with a physician visit, a diagnostic, and medications. Patients with complicated mononucleosis incur slightly more costs due to more physician visits (to a specialist) and more expensive diagnostics.
VACCINE DEVELOPMENT
The committee assumed that the development of an EBV vaccine is feasible and that licensure can occur within the time frame of its charge, but is not imminent. The estimates for the model are that it will take 15 years until licensure and that $390 million needs to be invested. Table 4–1 summarizes vaccine development assumptions for all vaccines considered in this report.
VACCINE PROGRAM CONSIDERATIONS
Target Population
The committee’s model assumes that immunization with this vaccine will occur during puberty. As described in the body of the report, for these purposes, that is set at 12 years of age. Both males and females would receive the immunization. It is estimated that only 50% of the target population will accept the immunization.
Vaccine Schedule, Efficacy, and Costs
The committee estimated that this would be a relatively low-cost vaccine, costing $50 per dose. Vaccine administration would cost an additional $10. The committee has accepted default assumptions for this vaccine that it will require a series of 3 doses and that effectiveness will be 75%. Table 4–1 summarizes vaccine program assumptions for all vaccines considered in this report.
RESULTS
If a vaccine program for EBV were implemented today and the vaccine was 100% efficacious and utilized by 100% of the target population, the annualized
present value of the QALYs gained would be 630. Using committee assumptions of less-than-ideal efficacy and utilization and including time and monetary costs until a vaccine program is implemented, the annualized present value of the QALYs gained would be 130. Although the number of people experiencing uncomplicated mononucleosis is far greater than those experiencing complications, slightly more than half of the QALYs lost are attributable to complicated mononucleosis due to the much lower HUI value and the longer duration.
If a vaccine program for EB V were implemented today and the vaccine was 100% efficacious and utilized by 100% of the target population, the annualized present value of the health care costs saved would be $12.6 million. Using committee assumptions of less-than-ideal efficacy and utilization and including time and monetary costs until a vaccine program is implemented, the annualized present value of the health care costs saved would be $2.6 million.
If a vaccine program for EBV were implemented today and the vaccine was 100% efficacious and utilized by 100% of the target population, the annualized present value of the program cost would be $680 million. Using committee assumptions of less-than-ideal efficacy and utilization and including time and monetary costs until a vaccine program is implemented, the annualized present value of the program cost would be $ 190 million.
Using committee assumptions of time and costs until licensure, the fixed cost of vaccine development has been amortized and is $11.7 million for a EBV vaccine.
If a vaccine program were implemented today and the vaccine were 100% efficacious and utilized by 100% of the target population, the annualized present value of the cost per QALY gained is $1.1 million. Using committee assumptions of less-than-ideal utilization and including time and monetary costs until a vaccine program is implemented, the annualized present value of the cost per QALY gained is $ 1.5 million.
See Chapters 4 and 5 for details on the methods and assumptions used by the committee for the results reported.
READING LIST
Sumaya CV. Epstein-Barr Virus. In: Textbook of Pediatric Infectious Diseases. RD Feigin and JD Cherry eds. Philadelphia, PA: WB Saunder Company, 1992, pp. 1547–1557.
Schooley RT. Epstein-Barr Virus (Infectious Mononucleosis). In: Principles and Practice of Infectious Diseases. GL Mandell, JE Bennett, Dolin R eds. New York, NY: Churchill Livingstone, 1995, pp. 1364–1376.
U.S. Bureau of the Census. Statistical Abstract of the U.S.: 1995 (115th edition). Washington, D.C. 1995.
