The American Journal of Managed Care March 2010
Cost-Effectiveness of Pneumococcal Polysaccharide Vaccine Among Healthcare Workers During an Influenza Pandemic
Pneumococcal polysaccharide vaccination of healthcare workers during an influenza pandemic is cost-effective from a societal perspective but not from a hospital perspective without external subsidy.
In this analysis, PPV is an economically reasonable strategy to be considered for healthcare workers during an influenza pandemic from a societal perspective, with robust results in 1-way sensitivity analyses and a high likelihood of cost-effectiveness in a probabilistic sensitivity analysis. Our results are comparable to findings of a recent analysis by the CDC examining PPV use in critical infrastructure personnel (eg, healthcare workers and utility workers).17,26 The investigators estimated 35,000 invasive and non-IPD cases in a population of 20 million, or an attack rate of 175 per 100,000. Using their age-specific hospitalization rates and assuming that 25% of workers are 50 years or older, the pneumococcal disease hospitalization rate was about 25.8 per 100,000. If half of those hospitalized had IPD, then the IPD rate was 12.9 cases per 100,000, slightly less than our calculated IPD rate in healthcare workers, 13.7 cases per 100,000. Using 0.942 (ie, 12.9 of 13.7), the IPD relative risk derived from their study, in our analysis produces an incremental cost-effectiveness ratio of $6419 per QALY gained. This value falls within the range of their discounted life-years saved result of $37,320 (95% confidence interval, $5865-$80,359). Unlike our analysis, the CDC study did not use utilities or account for disability or PPV effects beyond the pandemic year.17
On the other hand, from the hospital perspective, PPV of healthcare workers costs $1676 per employee absence day avoided, which most hospitals would consider a steep premium to pay for a small expected return. Our analysis highlights the dilemma many hospital systems face in trying to do the right thing from a societal standpoint, while at the same time attempting to remain fiscally sound. Managed care faces this tension of hospital versus societal perspectives as it seeks to maximize health in a cost-effective way. Even with a heightened risk of pneumococcal disease during an influenza pandemic, the risk of IPD would probably remain less than 1% for healthcare workers, and this fact might lead hospital systems to defer PPV for their workers unless some subsidy to defray vaccination costs was available. We did not include the possibility that healthcare workers would infect other workers or patients or that hospitals would be unable to meet staffing needs due to absenteeism; therefore, our estimates are conservative. Maintenance of appropriate staffing levels is a priority in managed care. Although expensive from the hospital perspective, vaccination may lead workers to perceive themselves as better protected and to be more willing to work in the face of a pandemic. Given that PPV is less expensive than many other occupationally indicated vaccines, it may be reasonable to consider PPV as a means to allay worker concerns about complications of pandemic influenza.
From a societal standpoint, PPV administration to healthy healthcare workers at the onset of a pandemic has pros and cons. Vaccination is likely to reduce IPD27-30 and in healthy workers may reduce pneumococcal pneumonia.31 However, concerns exist about vaccine efficacy against noninvasive pneumonia and about hyporesponsiveness to subsequent vaccination, also known as tolerance.4 If hyporesponsiveness occurs following PPV, it might simply shift the burden of pneumococcal disease from the time of the pandemic to later in the life of the healthcare worker, without changing the cumulative incidence. Repeat doses of PPV later in life are generally safe18; therefore, the concern is not safety at the time of vaccination or of repeat vaccination years later but of potential hyporesponsiveness. Another potential limitation of our analysis is that recent PPV recommendations32 have added smoking and asthma to the list of comorbid conditions for which vaccination before age 65 years is recommended and could further lessen the effect of healthcare worker vaccination given the considerable proportion of workers falling into these categories.
Because of the current absence of clinical trial data and for the foreseeable future, we used a Markov model to synthesize available data. We also used a series of conservative estimates and assumptions, including PPV effectiveness against IPD, not pneumococcal pneumonia, although some data suggest that PPV may have effectiveness against pneumonia in healthy adults.31 Despite these assumptions, vaccination of healthcare workers with PPV was cost-effective from the societal perspective. Limitations include the unknown increased IPD risk in a pandemic and the inability to address PPV effect on hyporesponsiveness to future pneumococcal vaccines, either polysaccharide or conjugate, the latter of which may be licensed for adults in the future. We used longer time horizons than prior analyses; this has the advantage of not being limited to pandemic effects but has the disadvantage of not accounting for future new vaccines and changes in epidemiology. Because we used a 15-year time frame and a single PPV in those who were previously unvaccinated and because current CDC recommendations only call for PPV revaccination at age 65 years for those vaccinated before that age, we did not include revaccination as part of our analyses of current workers. If a longer time horizon was examined or if hyporesponsiveness occurred, greater costs per QALY gained would result.
In conclusion, vaccinating all healthcare workers to protect against pneumococcal disease during a pandemic influenza outbreak is likely to be economically reasonable according to a societal perspective in an analysis biased against vaccination. However, when analyzed from a hospital perspective, PPV is expensive, and the small risk of illness might prevent hospital implementation unless vaccination is externally subsidized.
Author Affiliations: From the Section of Decision Sciences and Clinical Systems Modeling (KJS, MSR), the Department of Family Medicine and Clinical Epidemiology (MR, MPN, RKZ), and the Department of Behavioral and Community Health Sciences (RKZ), University of Pittsburgh, Pittsburgh PA.
Funding Source: This study was supported by grant R01AI076256 from the National Institute of Allergy and Infectious Diseases. Its contents are the responsibility of the authors and do not necessarily reflect the official views of the National Institutes of Health.
Author Disclosures: Drs Nowalk and Zimmerman report receiving grants from Merck & Co, Inc, and MedImmune. The other authors (KJS, MR, MSR) report no relationship or financial interest with any entity that would pose a conflict of interest with the subject matter of this article.
Authorship Information: Concept and design (KJS, MSR, RKZ); acquisition of data (KJS, MR, RKZ); analysis and interpretation of data (KJS, RKZ); drafting of the manuscript (KJS, MPN, RKZ); critical revision of the manuscript for important intellectual content (KJS, MPN, MSR); statistical analysis (MR); obtaining funding (KJS, RKZ); and administrative, technical, or logistic support (MR).
Address correspondence to: Kenneth J. Smith, MD, MS, Section of Decision Sciences and Clinical Systems Modeling, University of Pittsburgh, 200 Meyran Ave, Ste 200, Pittsburgh, PA 15213. E-mail: firstname.lastname@example.org.
1. National Center for Immunization and Respiratory Diseases, CDC; Centers for Disease Control and Prevention (CDC). Use of influenza A (H1N1) 2009 (monovalent) vaccine: recommendations of the Advisory Committee on Immunization Practices (ACIP), 2009. MMWR Recomm Rep. 2009;58(RR-10):1-8.
2. Morens DM, Taubenberger JK, Fauci AS. Predominant role of bacterial pneumonia as a cause of death in pandemic influenza: implications for pandemic influenza preparedness. J Infect Dis. 2008;198(7):962-970.
3. Brundage JF. Interactions between influenza and bacterial respiratory pathogens: implications for pandemic preparedness. Lancet Infect Dis. 2006;6(5):303-312.
4. O’Brien KL, Hochman M, Goldblatt D. Combined schedules of pneumococcal conjugate and polysaccharide vaccines: is hyporesponsiveness an issue? Lancet Infect Dis. 2007;7(9):597-606.
5. Arias E. United States life tables, 2002. Natl Vital Stat Rep. 2004;53(6):1-38.
6. Musher DM. Streptococcus pneumoniae. In: Mandell GL, Douglas RG, Bennett JE, Dolin R, eds. Principles and Practice of Infectious Diseases. New York, NY: Elsevier/Churchill Livingstone; 2005.
7. Gold M, Siegel J, Russell L, Weinstein M. Cost-Effectiveness in Health and Medicine. New York, NY: Oxford University Press; 1996.
8. Centers for Disease Control and Prevention. Active Bacterial Core surveillance report, Emerging Infections Program Network, Streptococcus pneumoniae, 2007. Updated December 1, 2008. http://www.cdc.gov/abcs/reports-findings/survreports/spneu07.pdf. Accessed March 3, 2010.
9. US Department of Health and Human Services. The registered Registered Nurses. Updated 2004. http://bhpr.hrsa.gov/healthworkforce/rnsurvey04/3.htm. Accessed October 1, 2009.
10. US Department of Health and Human Services. National Center for Health Workforce Analysis: supply, demand, and use of licensed practical nurses. Updated November 1, 2004. http://bhpr.hrsa.gov/healthworkforce/reports/lpn/LPN1_5.htm. Accessed October 1, 2009.
11. Centers for Disease Control and Prevention (CDC). Bacterial coinfections in lung tissue specimens from fatal cases of 2009 pandemic influenza A (H1N1): United States, May-August 2009. MMWR Morb Mortal Wkly Rep. 2009;58(38):1071-1074.
12. Smith KJ, Zimmerman RK, Lin CJ, et al. Alternative strategies for adult pneumococcal polysaccharide vaccination: a cost-effectiveness analysis. Vaccine. 2008;26(11):1420-1431.
13. Sisk JE, Whang W, Butler JC, Sneller VP, Whitney CG. Cost-effectiveness of vaccination against invasive pneumococcal disease among people 50 through 64 years of age: role of comorbid conditions and race. Ann Intern Med. 2003;138(12):960-968.
14. Centers for Disease Control and Prevention. CDC vaccine price list. 2009. http://www.cdc.gov/vaccines/programs/vfc/cdc-vac-price-list.htm. Accessed July 8, 2009.
15. Centers for Medicare and Medicaid Services. Physician Fee Schedule look-up. 2007. http://www.cms.hhs.gov/PFSlookup/. Accessed August 29, 2009.
16. Centers for Medicare and Medicaid Services. Payment allowances for the influenza virus vaccine (CPT 90655, 90656, 90657, and 90658) and the pneumococcal vaccine (CPT 90732) when payment is based on 95 percent of the average wholesale price (AWP). 2007. http://www.cms.hhs.gov/MLNMattersArticles/downloads/MM4109.pdf. Accessed August 27, 2009.
17. Messonnier ML, Zhou F, Moore MR. Cost-effectiveness of using 23-valent pneumococcal polysaccharide vaccine to prevent pneumococcal pneumonia in target population groups during an influenza pandemic in the United States. Updated 2009. http://www.cdc.gov/vaccines/recs/acip/downloads/mtg-slides-feb09/07-2-pneu.pdf. Accessed August 11, 2009.
18. Jackson LA, Benson P, Sneller VP, et al. Safety of revaccination with pneumococcal polysaccharide vaccine. JAMA. 1999;281(3):243-248.
19. US Bureau of Labor Statistics. Average hourly earnings of production workers, general medical and surgical hospitals, 2006. Updated 2008. Accessed August 7, 2009.
20. Kamal-Bahl SJ, Pantely S, Pyenson B, Alexander CM. Employer-paid nonmedical costs for patients with diabetes and end-stage renal disease. Prev Chronic Dis. 2006;3(3):eA83. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1636708/?tool=pubmed. Accessed February 13, 2010.
21. Gold MR, Franks P, McCoy KI, Fryback DG. Toward consistency in cost-utility analyses: using national measures to create condition-specific values. Med Care. 1998;36(6):778-792.
22. Shapiro ED, Berg AT, Austrian R, et al. The protective efficacy of polyvalent pneumococcal polysaccharide vaccine. N Engl J Med. 1991;325(21):1453-1460.
23. Braithwaite RS, Meltzer DO, King JT Jr, Leslie D, Roberts MS. What does the value of modern medicine say about the $50,000 per quality-adjusted life-year decision rule? Med Care. 2008;46(4):349-356.
24. Laupacis A, Feeny D, Detsky AS, Tugwell PX. How attractive does a new technology have to be to warrant adoption and utilization? tentative guidelines for using clinical and economic evaluations. CMAJ. 1992;146(4):473-481.
25. Hirth RA, Chernew ME, Miller E, Fendrick AM, Weissert WG. Willingness to pay for quality-adjusted life year: in search of a standard. Med Decis Making. 2000;20(3):332-342.
26. Moore MR; Advisory Committee on Immunization Practices. Use of 23-valent pneumococcal polysaccharide vaccine for prevention of pneumococcal pneumonia during an influenza pandemic: potential role among critical infrastructure personnel. http://www.cdc.gov/vaccines/recs/ACIP/downloads/mtg-slides-feb09/07-1-pneu.pdf. Updated February 22, 2009. Accessed August 11, 2009.
27. Conaty S, Watson L, Dinnes J, Waugh N. The effectiveness of pneumococcal polysaccharide vaccines in adults: a systematic review of observational studies and comparison with results from randomised controlled trials. Vaccine. 2004;22(23-24):3214-3224.
28. Cornu C, Yzèbe D, Léophonte P, Gaillat J, Boissel JP, Cucherat M. Efficacy of pneumococcal polysaccharide vaccine in immunocompetent adults: a meta-analysis of randomized trials. Vaccine. 2001;19(32):4780-4790.
29. Dear K, Holden J, Andrews R, Tatham D. Vaccines for preventing pneumococcal infection in adults [update in Cochrane Database Syst Rev. 2008;(1):CD000422]. Cochrane Database Syst Rev. 2003;(4):CD000422.
30. Jackson LA, Neuzil KM. Pneumococcal polysaccharide vaccines. In: Plotkin SA, Orenstein WA, Offit PA, eds. Vaccines. Philadelphia, PA: Saunders Elsevier Inc; 2008:569-604.
31. Yekutiel P. Lessons from the big eradication campaigns. World Health Forum. 1981;2:465-490.
32. Centers for Disease Control and Prevention. ACIP provisional recommendations for use of pneumococcal vaccines. Updated October 22, 2008. http://www.cdc.gov/vaccines/recs/provisional/downloads/pneumo-Oct-2008-508.pdf. Accessed August 29, 2009.