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Bulletin of Mathematical Biology

, Volume 78, Issue 2, pp 185–209 | Cite as

Modeling Importations and Exportations of Infectious Diseases via Travelers

  • Luis Fernandez Lopez
  • Marcos Amaku
  • Francisco Antonio Bezerra Coutinho
  • Mikkel Quam
  • Marcelo Nascimento Burattini
  • Claudio José Struchiner
  • Annelies Wilder-Smith
  • Eduardo MassadEmail author
Original Article

Abstract

This paper is an attempt to estimate the risk of infection importation and exportation by travelers. Two countries are considered: one disease-free country and one visited or source country with a running endemic or epidemic infectious disease. Two models are considered. In the first model (disease importation), susceptible individuals travel from their disease-free home country to the endemic country and come back after some weeks. The risk of infection spreading in their home country is then estimated supposing the visitors are submitted to the same force of infection as the local population but do not contribute to it. In the second model (disease exportation), it is calculated the probability that an individual from the endemic (or epidemic) country travels to a disease-free country in the condition of latent infected and eventually introduces the infection there. The input of both models is the force of infection at the visited/source country, assumed known. The models are deterministic, but a preliminary stochastic formulation is presented as an appendix. The models are exemplified with two distinct real situations: the risk of dengue importation from Thailand to Europe and the risk of Ebola exportation from Liberia to the USA.

Keywords

Infectious disease importation Infectious disease exportation Travelers Modeling Risk 

Notes

Acknowledgments

This study received partial funding from LIM01-HCFMUSP, HSP/ UNIFESP, CNPq, FAPESP, Ministry of Health (Fundo Nacional de Saúde, grant 27835/2012), and was also partially funded by DengueTools (22) under the Health theme of the Seventh Framework Programme of the European Community (Grant Agreement Number 282589), DengueTools: innovative tools and strategies for the surveillance and control of dengue. Open image in new window http://www.ncbi.nlm.nih.gov/pubmed/22451836 Open image in new window (Wilder-Smith et al. 2012).

Conflict of interest

The authors declare no conflict of interest.

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Copyright information

© Society for Mathematical Biology 2016

Authors and Affiliations

  • Luis Fernandez Lopez
    • 1
    • 2
  • Marcos Amaku
    • 1
  • Francisco Antonio Bezerra Coutinho
    • 1
  • Mikkel Quam
    • 3
  • Marcelo Nascimento Burattini
    • 1
    • 4
  • Claudio José Struchiner
    • 5
  • Annelies Wilder-Smith
    • 6
    • 7
  • Eduardo Massad
    • 1
    • 8
    Email author
  1. 1.School of MedicineUniversity of São PauloSão PauloBrazil
  2. 2.CIARAFlorida International UniversityMiamiUSA
  3. 3.Epidemiology and Global HealthUmeå UniversityUmeåSweden
  4. 4.Hospital São PauloEscola Paulista de MedicinaSão PauloBrazil
  5. 5.PROCCFIOCRUZRio de JaneiroBrazil
  6. 6.Lee Kong Chian School of MedicineNanyangSingapore
  7. 7.Technological UniversitySingaporeSingapore
  8. 8.London School of Hygiene and Tropical MedicineLondonUK

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