Skip to main content

Real-Time Assessment of the International Spreading Risk Associated with the 2014 West African Ebola Outbreak

  • Chapter
  • First Online:
Mathematical and Statistical Modeling for Emerging and Re-emerging Infectious Diseases

Abstract

The 2014 West African Ebola Outbreak is the largest Ebola virus disease (EVD) epidemic ever recorded, not only in number of cases but also in geographical extent. Unlike previous EVD outbreaks, the large number of cases observed in major cities with international airports raised the concern about the possibility of exportation of the infection in countries around the world. Starting in July 2014, we used the Global Epidemic and Mobility model to provide a real-time assessment of the potential international spread of the EVD epidemic. We modeled the unfolding of the outbreak in the most affected countries, considered different scenarios reflecting changes in the disease dynamic, and provided estimates for the probability of observing imported cases around the world for 220 countries. The model went through successive calibrations as more surveillance data were available, providing projections extending from a few weeks to several months. The results show that along the entire course of the epidemic the probability of observing cases outside of Africa was small, but not negligible, from September to November 2014. The inflection point of the epidemic occurred in late September and early October 2014 with a consistent longitudinal decrease in new cases, thus averting the status quo epidemic growth that could have seen hundreds of exported cases at the global scale in the following months.

This is a preview of subscription content, log in via an institution to check access.

Access this chapter

Subscribe and save

Springer+ Basic
$34.99 /Month
  • Get 10 units per month
  • Download Article/Chapter or eBook
  • 1 Unit = 1 Article or 1 Chapter
  • Cancel anytime
Subscribe now

Buy Now

Chapter
USD 29.95
Price excludes VAT (USA)
  • Available as PDF
  • Read on any device
  • Instant download
  • Own it forever
eBook
USD 84.99
Price excludes VAT (USA)
  • Available as EPUB and PDF
  • Read on any device
  • Instant download
  • Own it forever
Softcover Book
USD 109.99
Price excludes VAT (USA)
  • Compact, lightweight edition
  • Dispatched in 3 to 5 business days
  • Free shipping worldwide - see info
Hardcover Book
USD 109.99
Price excludes VAT (USA)
  • Durable hardcover edition
  • Dispatched in 3 to 5 business days
  • Free shipping worldwide - see info

Tax calculation will be finalised at checkout

Purchases are for personal use only

Institutional subscriptions

Similar content being viewed by others

References

  1. Feldmann, H., Geisbert, T.W.: Lancet 377, 849–62 (2011)

    Article  Google Scholar 

  2. World Health Organization. Ebola key facts. http://www.who.int/mediacentre/factsheets/fs103/en/

  3. ECDC: Outbreak of Ebola virus disease in West Africa. Third update (2014). Accessed 1 Aug 2014

    Google Scholar 

  4. Ebola ça Suffit Ring Vaccination Trial Consortium. BMJ 351, h3740 (2015)

    Google Scholar 

  5. Henao-Restrepo, A.M., Longini, I.M., Egger, M., Dean, N.E., Edmunds, W.J., Camacho, A., Carroll, M.W., Doumbia, M., Draguez, B., Duraffour, S., et al.: Lancet 386(9996), 857–866 (2015)

    Article  Google Scholar 

  6. World Health Organization: Ebola Situation Report. http://www.who.int/csr/disease/ebola/situation-reports/archive/en/. Accessed 15 Dec 2015

  7. World Health Organization: Statement on the 1st meeting of the IHR Emergency Committee on the 2014 Ebola outbreak in West Africa. http://www.who.int/mediacentre/news/statements/2014/ebola-20140808/en/. Accessed 15 Dec 2015

  8. Balcan, D., Hu, H., Goncalves, B., Bajardi, P., Poletto, C., et al.: BMC Med. 7, 45 (2009)

    Article  Google Scholar 

  9. Balcan, D., Colizza, V., Goncalves, B., Hu, H., Ramasco, J.J., et al.: Proc. Natl. Acad. Sci. 106, 21484–21489 (2009)

    Article  Google Scholar 

  10. Balcan, D., Goncalves, B., Hu, H., Ramasco, J.J., Colizza, V., et al.: J. Comput. Sci. 1, 132–145 (2010)

    Article  Google Scholar 

  11. Legrand, J., Grais, R., Boelle, P., Valleron, A., Flahault, A.: Epidemiol Infect 135, 610 (2007)

    Article  Google Scholar 

  12. Brockmann, D., Schaade, L., Verbee, L.: 2014 Ebola Outbreak. Worldwide Air-Transportation, Relative Import Risk and Most Probable Spreading Routes. http://rocs.hu-berlin.de/projects/ebola/

  13. Mekaru, S.: Ebola 2014: A Rapid Threat Assessment. The Disease Daily. (2014). http://healthmap.org/site/diseasedaily/article/ebola-2014-rapid-threat-assessment-8514

  14. Poletto, C., Gomes, M.F. C., Pastore y Piontti, A., Rossi, L., Bioglio, L., Chao, D. L.,Longini, I. M., Halloran, M. E., Colizza, V., Vespignani, A.: Euro Surveill 19(42), 20936 (2014). http://dx.doi.org/10.2807/1560-7917.ES2014.19.42.20936

  15. Tizzoni, M., Bajardi, P., Poletto, C., Ramasco, J.J., Balcan, D., et al.: BMC Med. 10, 165 (2012)

    Article  Google Scholar 

  16. Rvachev, L.A., Longini, I.M.: Math. Biosci. 75, 3–22 (1985)

    Article  MathSciNet  Google Scholar 

  17. Flahault, A., Valleron, A.: Math. Popul. Stud. 3, 161–171 (1992)

    Article  Google Scholar 

  18. Colizza, V., Barrat, A., Barthelemy, M., Valleron, A.J., Vespignani, A.: PLOS Med. 4, e13 (2007)

    Article  Google Scholar 

  19. GPWv3: Gridded Population of the World. Socio Economic Data and Aplications Center at Columbia University (2014)

    Google Scholar 

  20. IATA: International Air Transport Association (2014)

    Google Scholar 

  21. OAG: Official Airline Guide (2014)

    Google Scholar 

  22. Simini, F., Gonzalez, M.C., Maritan, A., Barabasi, A.L.: Nature 484, 96–100 (2012)

    Google Scholar 

  23. Halloran, M.E., Longini, I.M., Struchiner, C.J.: Design and Analysis of Vaccine Studies, pp. 63–84. Springer Science + Business Media, New York (2009)

    Google Scholar 

  24. Diekmann, O., Heesterbeek, J.: Mathematical Epidemiology of Infectious Diseases: Model Building, Analysis and Interpretation. Wiley, Chichester (2000)

    MATH  Google Scholar 

  25. van den Driessche, P., Watmough, J.: Math. Biosci. 180, 29–48 (2002)

    Article  MathSciNet  Google Scholar 

  26. Bwaka, M., Bonnet, M., Calain, P., Colebunders, R., Roo, A.D., et al.: J. Infect. Dis. 179, S1–S7 (1999)

    Article  Google Scholar 

  27. Ndambi, R., Akamituna, P., Bonnet, M., Tukadila, A., MuyembeTamfum, J., et al.: J. Infect. Dis. 179, S8–S10 (1999)

    Article  Google Scholar 

  28. Dowell, S., Mukunu, R., Ksiazek, T., Khan, A., Rollin, P., et al.: J. Infect. Dis. 179, S87–S91 (1999)

    Article  Google Scholar 

  29. Khan, A., Tshioko, F., Heymann, D., Guenno, B.L., Nabeth, P., et al.: J. Infect. Dis. 179, S76–S86 (1999)

    Article  Google Scholar 

  30. Rowe, A., Bertolli, J., Khan, A., Mukunu, R., Muyembe-Tamfum, J., et al.: J. Infect. Dis. 179, S28–S35 (1999)

    Google Scholar 

  31. World Health Organization: Disease Outbreaks News. http://www.who.int/csr/don/archive/disease/ebola/en/

  32. Chowell, G., Hengartner, N., Castillo-Chavez, C., Fenimore, P., Hyman, J.: J. Theor. Biol. 229, 119–126 (2004)

    Article  MathSciNet  Google Scholar 

  33. Ndanguza, D., Tchuenche, J.M., Haario, H.: Afr Mat 24, 55–68 (2011)

    Article  MathSciNet  Google Scholar 

  34. WHO Ebola Response Team: N Engl J Med 371:1481–1495 (2014)

    Google Scholar 

  35. WHO Ebola Response Team: N. Engl. J. Med 372:584–587 (2015)

    Google Scholar 

  36. Weitz, J.S., Dushoff, J.: Sci. Rep. 5, 8751 (2015)

    Google Scholar 

  37. Gomes, M.F.C., Pastore y Piontti, A., Rossi, L., Chao, D., Longini, I., Halloran, M.E., Vespignani, A.: PLOS Currents Outbreaks, edn. 1. 2014 Sep 2. (2014). doi:10.1371/currents.outbreaks.cd818f63d40e24aef769dda7df9e0da5

  38. Merler, S., Ajelli, M., Fumanelli, L., Gomes, M.F.C., Pastore y Piontti, A., Rossi, L., Longini, I.Jr, Halloran, M.E., Vespignani, A.: Lancet Infect. Dis. 15(2), 204–211 (2015)

    Google Scholar 

Download references

Acknowledgments

We acknowledge funding from DTRA-1-0910039 and MIDAS-National Institute of General Medical Sciences U54-GM111274. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. MFCG acknowledges CNPq-Brazil fellowship 314164/2014-6. We thank Nicole Samay for her invaluable help in the editing and preparation of the figures of the manuscript.

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to Alessandro Vespignani .

Editor information

Editors and Affiliations

Rights and permissions

Reprints and permissions

Copyright information

© 2016 Springer International Publishing Switzerland

About this chapter

Cite this chapter

Pastore-Piontti, A. et al. (2016). Real-Time Assessment of the International Spreading Risk Associated with the 2014 West African Ebola Outbreak. In: Chowell, G., Hyman, J. (eds) Mathematical and Statistical Modeling for Emerging and Re-emerging Infectious Diseases. Springer, Cham. https://doi.org/10.1007/978-3-319-40413-4_4

Download citation

Publish with us

Policies and ethics