Public health vaccination policies for containing an anthrax outbreak

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Abstract

Concern about biological weapons has raised questions about the most effective public health policies to contain an anthrax outbreak1,2,3. We developed a probability model to predict the impact of different anthrax antibiotic and vaccination policies. An anthrax outbreak can be significantly contained by minimizing the delay until initiation of antibiotic prophylaxis. However, even if mass distribution of antibiotics is completed within six days of the initial exposure, then at most about 70% of cases can be prevented. Post-exposure vaccination will not significantly increase that prevention rate if adherence to antibiotic regimens is similar or higher than that attained in the 2001 US outbreak4. However, post-exposure vaccination can be useful either in shortening the duration of a prolonged antibiotic regimen, in the event of an antibiotic-resistant strain, or if antibiotic adherence rates are very low. Here we show that a mass pre-exposure vaccination programme for the general population would require very high population coverage rates to significantly increase prevention rates from that achieved with targeted and rapid post-exposure prophylaxis programmes.

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Figure 1: Percentage of cases prevented versus delay of initiating mass distribution of antibiotics.
Figure 2: Days that antibiotic therapy can be shortened by post-exposure vaccination versus vaccine efficacy.

References

  1. 1

    Inglesby, T. V. et al. Anthrax as a biological weapon: medical and public health management. J. Am. Med. Assoc. 281, 1735–1745 (1999)

  2. 2

    Inglesby, T. V. et al. Anthrax as a biological weapon. Updated recommendations for management. J. Am. Med. Assoc. 287, 2236–2252 (2002)

  3. 3

    Centers for Disease Control. Notice to readers: use of anthrax vaccine in response to terrorism: supplemental recommendations of the Advisory Committee on Immunization Practices. Morb. Mortal. Wkly Rep. 51, 1024–1026 (2002)

  4. 4

    Jernigan, J. A. et al. Bioterrorism-related inhalation anthrax: The first 10 cases reported in the United States. Emerg. Infect. Dis. 17, 933–944 (2001)

  5. 5

    Joellenbeck, L., Zwanziger, L., Durch, J. & Strom, B. (eds) The Anthrax Vaccine: Is it Safe? Does it Work? (National Academy Press, Washington DC, 2002)

  6. 6

    National Institute of Allergy and Infectious Diseases. National Institute of Allergy and Infectious Diseases biodefense research agenda for CDC category A agents. 〈http://www.niaid.nih.gov/publications/bioterrorism.htm〉 (2002).

  7. 7

    Centers for Disease Control. Update: investigation of bioterrorism-related anthrax. Morb. Mortal. Wkly Rep. 50, 1008–1010 (2001)

  8. 8

    Shepard, C. W. et al. Antimicrobial post-exposure prophylaxis for anthrax: Adverse events and adherence. Emerg. Infect. Dis. 8, 1124–1132 (2002)

  9. 9

    Brookmeyer, R. & Blades, N. Prevention of inhalational anthrax in the U.S. outbreak. Science 295, 1861 (2002)

  10. 10

    Meselson, M. et al. The Sverdlovsk anthrax outbreak of 1979. Science 266, 1202–1208 (1994)

  11. 11

    Wein, L. M., Craft, D. L. & Kaplan, E. H. Emergency response to an anthrax outbreak. Proc. Natl Acad. Sci. USA 100, 4346–4351 (2003)

  12. 12

    Committee on Research and Development Needs for Improving Civilian Medical Response to Chemical and Biological Terrorism Incidents. Chemical and Biological Terrorism (National Academy Press, Washington DC, 1999)

  13. 13

    Kaplan, E. H., Craft, D. L. & Wein, L. M. Emergency response to a smallpox attack: the case for mass vaccination. Proc. Natl Acad. Sci. USA 99, 10935–10940 (2002)

  14. 14

    Bozette, S. et al. A model for a smallpox-vaccination policy. N. Engl. J. Med. 348, 416–425 (2003)

  15. 15

    Halloran, M. E., Longini, I. M. Jr, Nizam, A. & Yang, Y. Containing bioterrorist smallpox. Science 298, 1428–1432 (2002)

  16. 16

    Ferguson, N. M. et al. Planning for smallpox outbreak. Nature 425, 681–685 (2003)

  17. 17

    Fraser, C., Riley, S., Anderson, R. M. & Ferguson, N. M. Factors that make an infectious disease outbreak controllable. Proc. Natl Acad. Sci. USA 101, 6146–6151 (2004)

  18. 18

    Kaufmann, A., Meltzer, M. & Schmid, G. The economic impact of a bioterrorist attack: Are prevention and post attack intervention programs justifiable? Emerg. Infect. Dis. 3, 83–94 (1997)

  19. 19

    Centers for Disease Control and Prevention. Mass antibiotic dispensing: A primer. 〈http://www.phppo.cdc.gov/phtn/antibiotic/default.asp〉 (June 2004).

  20. 20

    Brookmeyer, R., Johnson, E. & Bollinger, R. Modeling the optimum duration of antibiotic prophylaxis in an anthrax outbreak. Proc. Natl Acad. Sci. USA 100, 10129–10132 (2003)

  21. 21

    Brachman, P. S. Inhalation anthrax. Ann. NY Acad. Sci. 353, 83–93 (1980)

  22. 22

    Ross, J. M. The pathogenesis of anthrax following the administration of spores by the respiratory route. J. Pathol. Bacteriol. 73, 484–494 (1957)

  23. 23

    Friedlander, A. M. et al. Post-exposure prophylaxis against experimental inhalation anthrax. J. Infect. Dis. 167, 1239–1242 (1993)

  24. 24

    Friedlander, A. M. Anthrax: clinical features, pathogenesis and potential biological warfare threat. Curr. Clin. Top. Infect. Dis. 20, 335–349 (2000)

  25. 25

    Cieslak, T. J. & Edward, M. E. Clinical and epidemiological principles of anthrax. Infect. Dis. 5, 51–55 (1999)

  26. 26

    Henderson, D. W., Peakcock, S. & Belton, F. C. Observations on the prophylaxis of experimental pulmonary anthrax in the monkey. J. Hyg. (Lond.) 54, 28–35 (1956)

  27. 27

    Haas, C. N. On the risk of mortality to primates exposed to anthrax spores. Risk Anal. 22, 189–193 (2002)

  28. 28

    Watson, A. & Keir, D. Information on which to base assessments of risk from environmental contaminated with anthrax spores. Epidemiol. Infect. 113, 479–490 (1994)

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Acknowledgements

The authors acknowledge the comments of the Anthrax Modeling Working Group of the Secretary's Council on Public Health Preparedness of the Department of Health and Human Services. This research was partially funded by the Fogarty International Center and a grant from the National Institute of Allergy and Infectious Diseases.

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Correspondence to Ron Brookmeyer.

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The authors declare that they have no competing financial interests.

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Brookmeyer, R., Johnson, E. & Bollinger, R. Public health vaccination policies for containing an anthrax outbreak. Nature 432, 901–904 (2004) doi:10.1038/nature03087

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