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Instituto Nacional de Salud Pública

2011, Number 1

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salud publica mex 2011; 53 (1)

A model for the A(H1N1) epidemic in Mexico, including social isolation

Velasco-Hernández JX, Leite MCA

Language: English
References: 20
Page: 40-47
PDF size: 391.54 Kb.


ABSTRACT

Objective. We present a model for the 2009 influenza epidemic in Mexico to describe the observed pattern of the epidemic from March through the end of August (before the onset of the expected winter epidemic) in terms of the reproduction number and social isolation measures. Material and Methods. The model uses a system of ordinary differential equations. Computer simulations are performed to optimize trajectories as a function of parameters. Results. We report on the theoretical consequences of social isolation using published estimates of the basic reproduction number. The comparison with actual data provides a reasonable good fit. Conclusions. The pattern of the epidemic outbreak in Mexico is characterized by two peaks resulting from the application of very drastic social isolation measures and other prophylactic measures that lasted for about two weeks. Our model is capable of reproducing the observed pattern.


REFERENCES

  1. Neumann G, Noda T, Kawaoka Y. Emergence and pandemic potential of swine-origin H1N1 influenza virus. Nature 2009;459:931-939.

  2. Earn DJD, Dushoff J, Levin SA. Ecology and evolution of the flu. TRENDS in Ecology and Evolution 2002;17:334-340.

  3. Ministry of Health. Estadísticas de la epidemia. Influenza A(H1N1). Mexico: Ministry of Health, 2009. [Accessed on August 21, 2009]Available at: http://portal.salud.gob.mx/contenidos/noticias/influenza/estadisticas.html

  4. Fraser C, Donnelly CA, Cauchemez S, Hange WP, Van Kerkhove MD, Hollingsworth TD, et al. Pandemic potential of a strain of influenza A (H1N1): early findings. Science 2009;324(5934):1557-1561.

  5. Cohen J. Past pandemics provide mixed clues to H1N1’s next moves. Science 2009;324:996-997.

  6. Park AW, Glass K. Dynamic patterns of avian and human influenza in east and southeast Asia. Lancet Infect Dis 2007;7(8):543-548.

  7. Cruz-Pacheco G, Duran L, Esteva L, Minzoni AA, López-Cervantes L, Panayotaros P, et al. Modelling of the influenza A(H1N1)V outbreak in Mexico City, April-May 2009, with control sanitary measures. Euro Surveill 2009;14 (2).

  8. Tuite AR, Greer AL, Whelan M, et al. Estimated epidemiologic parameters and morbidity associated with pandemic H1N1 influenza. CMAJ 2009;182(2):131-136.

  9. Pourbohloul B, Ahued A, Davoudi B, Meza R, Meyers LA, Skowronski DM, et al. Initial Human Transmission Dynamics of the Pandemic (H1N1) 2009 Virus In North America : Methods. Influenza Resp Viruses 2009;3(5):215-222.

  10. Chowell G, Nishiura H, Bettencourt LMA. Comparative estimation of the reproduction number for pandemic influenza from daily case notification data. J R Soc Interface 2007;4(12):155-166.

  11. Chowell G, Ammon CE, Hengartner NW, Hyman JM. Transmission dynamics of the great influenza pandemic of 1918 in Geneva, Switzerland: assessing the effects of hypothetical interventions. J Theor Biol 2006;241:193-204.

  12. Boelle PY, Bernillon P, Desenclos JC. A preliminary estimation of the reproduction ratio for new influenza A(H1N1) from the outbreak in Mexico, March-April 2009. Euro Surveill 2009;14:10-13.

  13. Nishiura H, Castillo-Chavez C, Safan M, Chowell G. Transmission potential of the new influenza A(H1N1) virus and its age-specificity in Japan. Euro Surveill 2009;14(22):pii=19227.

  14. Massad E, Burattini MN, Coutinho FAB, Lopez LF. The 1918 influenza A epidemic in the city of São Paulo, Brazil. Med Hypotheses 2007;68(2):442-445.

  15. Mills CE, Robins JM, Lipsitch M. Transmissibility of the 1918 pandemic influenza. Nature 2004;432:904-906.

  16. Lessler J, Reich NG, Brookmeyer R, Perl TM, Nelson KE, Cummings DA. Incubation periods of acute respiratory viral infections: a systematic review. Lancet Infect Dis 2009;9:291-300.

  17. Epstein JM, Parker J, Cummings D, Hammond RA. Coupled contagion dynamics of fear and disease: mathematical and computational explorations. PLoS ONE 2008;3(12):e3955.

  18. Caley P, Philp DJ, McCracken K. Quantifying social distancing arising from pandemic influenza. J R Soc Interface 2005;5:631-639.

  19. Fajardo-Dolci G, Hernandez-Torres F, Santacruz-Varela J, Rodríguez-Suárez J, Lamy P, et al. Perfil epidemilógico de la mortalidad por influenza humana A (H1N1) en México. Salud Publica Mex 2009;51(5):361-371.

  20. Grijalva-Otero I, Talavera JO, Solorzano-Santos F, et al. Critical analysis of deaths due to atypical pneumonia during the onset of the influenza A(H1N1) virus pandemic. Arch Med Res 2009;40(8):662-668.




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