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Dynamic Epidemic Model for Influenza with Clinical Complications

Published online by Cambridge University Press:  02 January 2015

Sen-Te Wang
Affiliation:
Department of Family Medicine, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan Department of Family Medicine, Taipei Medical University Hospital, Taipei, Taiwan
Li-Sheng Chen
Affiliation:
School of Oral Hygiene, College of Oral Medicine, Taipei Medical University, Taipei, Taiwan
Long-Teng Lee
Affiliation:
Department of Family Medicine, National Taiwan University Hospital, Taipei, Taiwan
Hsiu-Hsi Chen*
Affiliation:
Division of Biostatistics, Institute of Epidemiology/Center for Biostatistics, College of Public Health, National Taiwan University, Taipei, Taiwan
*
College of Public Health, National Taiwan University, Room 533, No. 17, Hsu-Chow Road, Taipei, Taiwan 100 ([email protected])

Abstract

Objective.

To incorporate clinical complications in the susceptible-infectious-recovered model to estimate parameters needed in dynamic changes of infectious diseases and to further evaluate the impact of disease-controlling methods.

Methods.

We developed a new extended epidemic model that incorporates of disease-related complications. This model was applied to empirical data on influenza during the epidemic season of 2001–2002 in Taipei County, Taiwan, to estimate the transmission parameters that were converted to the basic reproductive rate (R0). The proposed model, in conjunction with estimated parameters, was applied in quantifying the efficacy of different preventive strategies.

Results.

During the study period there were 5 outbreaks of influenza. The estimated transmission probability for outbreak 1 was 0.135, with corresponding estimate of R0, 2.7; for outbreak 2, 0.165, with estimated R0, 3.3; for outbreak 3, 0.15, with R0, 4.5; for outbreak 4, 0.165, with R0, 5; and for outbreak 5, 0.165, with R0 5. The efficacy of antiviral prophylaxis to reduce the total episodes was 18% (95% CI, 15%–21%) under the coverage rate of 30%, 31% (95% CI, 26%–36%) under the coverage rate of 50%, and 73% (95% CI, 59%–90%) under the coverage rate of 80%. The corresponding figures for the efficacy of vaccination were 17% (95% CI, 15%–20%), 41% (95% CI, 35%–48%), and 76% (95% CI, 61%–95%). Combination of both methods would yield efficacy of 32% (95% CI, 28%–38%), 59% (95% CI, 49%–71%), and 88% (95% CI, 66%–118%), respectively.

Conclusions.

We demonstrate how to apply a novel extended model to empirical surveillance data of an influenza study for estimating parameters pertaining to dynamic changes in the infection process. These parameters were further used to evaluate the impact of antiviral prophylaxis alone, vaccination alone, or the use of both methods.

Type
Original Articles
Copyright
Copyright © The Society for Healthcare Epidemiology of America 2011

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References

1. Kermack, WO, McKendrick, AG. A contribution to the mathematical theory of epidemics. Proc R Soc Lond A 1927;115:700721.Google Scholar
2. Anderson, RM, May, RM. Infectious Diseases of Humans: Dynamics and Control. Oxford: Oxford University Press, 1992.Google Scholar
3. Diekmann, O, Heesterbeek, JAP. Mathematical epidemiology of infectious diseases: model building analysis and interpretation. Wiley Series in Mathematical and Computational Biology. New York: Wiley; 2000.Google Scholar
4. Gomes, MGM, White, LJ, Medley, GF. Infection, reinfection and vaccination under suboptimal immune protection: epidemiological perspectives. J Theoret Biol 2004;228:539549.CrossRefGoogle ScholarPubMed
5. Grenfell, BT, Bjornstad, ON, Kappey, J. Traveling waves and spatial hierarchies in measles epidemics. Nature 2001;414:716723.Google Scholar
6. Becker, NG, Rouderfer, V. Simultaneous control of measles and rubella by multidose vaccination schedules. Math Biosci 1996; 131:81102.Google Scholar
7. Andreasen, V, Lin, J, Levin, SA. The dynamics of cocirculating influenza strains conferring partial cross-immunity. J Math Biol 1997;35:825842.Google Scholar
8. Ackerman, E, Longini, IM Jr, Seaholm, SK, Hedin, AS. Simulation of mechanisms of viral interference in influenza. Int J Epidemiol 1990;19:444454.Google Scholar
9. Deguen, S, Flahault, A. Impact on immunization of seasonal cycle of chickenpox. Eur J Epidemiol 2000;16:11771181.CrossRefGoogle ScholarPubMed
10. Osborne, K, Gay, NJ, Hesketh, L, Morgan-Capner, P, Miller, E. Ten years of serological surveillance in England and Wales: methods, results, implications and action. Int J Epidemiol 2000;29:362368.Google Scholar
11. Hethcote, HW. Simulations of pertussis epidemiology in the United States: effects of adult booster vaccinations. Math Biosci 1999;158:4773.Google Scholar
12. van Boven, M, de Melker, HE, Schellekens, JFP, Kretzschmar, M. Waning immunity and sub-clinical infection in an epidemic model: implications for pertussis in the Netherlands. Math Biosci 2000;164:161182.CrossRefGoogle Scholar
13. Vynnycky, E, Fine, PEM. The natural history of tuberculosis: the implications of age-dependent risks of disease and the role of reinfection. Epidemiol Infect 1997;119:183201.Google Scholar
14. Feng, Z, Castillo-Chavez, C, Capurro, AF. A model for tuberculosis with exogenous reinfection. Theoret Popul Biol 2000;57:235247.Google Scholar
15. White, LJ, Waris, M, Cane, PA, Nokes, DJ, Medley, GF. The transmission dynamics of groups A and B human respiratory syncytial virus (hRSV) in England and Wales and Finland: seasonality and cross-protection. Epidemiol Infect 2005;133:279289.Google Scholar
16. Cane, PA. Molecular epidemiology of respiratory syncytial virus. Rev Med Virol 2001;11:103116.Google Scholar
17. Weber, A, Weber, M, Milligan, P. Modeling epidemics caused by respiratory syncytial virus (RSV). Math Biosci 2001;172:95113.Google Scholar
18. Hay, AJ, Gregory, V, Douglas, AR, Lin, YP. The evolution of human influenza viruses. Philos Trans R Soc Lond B 2001;356:18611870.CrossRefGoogle ScholarPubMed
19. Earn, DJD, Dushoff, J, Levin, SA. Ecology and evolution of the flu. Trends Ecol Evol 2002;17:334340.Google Scholar
20. Rothman, KJ, Greenland, A. Modern Epidemiology. Philadelphia: Lippincott-Raven, 1998:chap 27.Google Scholar
21. Shih, SR, Chen, GW, Yang, CC, et al. Laboratory-based surveillance and molecular epidemiology of influenza virus in Taiwan. J Clin Microbiol 2005;43:16511661.Google Scholar
22. Anderson, R, May, R. Population biology of infectious diseases: part I. Nature 1979;280:361.Google Scholar
23. Longini, IM Jr, Halloran, EM, Nizam, A, and Yang, Y. Containing pandemic influenza with antiviral agents. Am J Epidemiol 2004; 159:623633.Google Scholar
24. Hayden, FG, Aoki, FY. Amantadine, rimantadine, and related agents, antiviral agents. In: Yu, V, Meigan, T, Barriere, S, eds. Antimicrobial Therapy and Vaccines. Baltimore: Williams & Wilkins, 1999:13441365.Google Scholar
25. Hayden, FG, Gubareva, LV, Monto, AS, et al. Inhaled zanamivir for the prevention of influenza in families. N Engl J Med 2000; 343:12821289.Google Scholar
26. Monto, AS, Robinson, DP, Herlocher, ML, et al. Zanamivir in the prevention of influenza among healthy adults: a randomized controlled trial. JAMA 1999;282:3135.Google Scholar
27. Welliver, R, Monto, AS, Carewicz, O, et al. Effectiveness of oseltamivir in preventing influenza in household contacts: a randomized controlled trial. JAMA 2001;285:748754.Google Scholar
28. Galbraith, AW, Oxford, JS, Schild, GC, et al. Study of 1-adaman-tanamine hydrochloride used prophylactically during the Hong Kong influenza epidemic in the family environment. Bull World Health Organ 1969;41:677682.Google Scholar