Volume 71, Issue 5
  • ISSN: 0002-9637
  • E-ISSN: 1476-1645


We use spatially continuous satellite data as a correlate of precipitation within tropical Africa and show that the majority of documented Ebola hemorrhagic fever outbreaks were closely associated with sharply drier conditions at the end of the rainy season. We propose that these trigger events may enhance transmission of Ebola virus from its cryptic reservoir to humans. These findings suggest specific directions to help understand the sylvatic cycle of the virus and may provide early warning tools to detect possible future outbreaks of this enigmatic disease.


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  1. Peters CJ, LeDuc JW, 1999. An introduction to Ebola: the virus and the disease. J Infect Dis 179 : 9–16. [Google Scholar]
  2. World Health Organization, 1976. Ebola hemorrhagic fever in Sudan, 1976. Bull World Health Organ 56 : 247–270. [Google Scholar]
  3. World Health Organization, 1976. Ebola hemorrhagic fever in Zaire, 1976. Bull World Health Organ 56 : 271–293. [Google Scholar]
  4. Heymann DL, Weisfeld JS, Webb PA, Johnson KM, Cairns T, Berquist H, 1980. Ebola hemorrhagic fever: Tandala, Zaire, 1977–1978. J Infect Dis 142 : 372–376. [Google Scholar]
  5. Baron RC, McCormick JB, Zubeir OA, 1983. Ebola virus disease in southern Sudan: hospital dissemination and intrafamilial spread. Bull World Health Organ 61 : 997–1003. [Google Scholar]
  6. Formenty P, Boesch C, Wyers M, Steiner C, Donati F, Dind F, Walker F, Le Guenno B, 1999. Ebola virus outbreak among wild chimpanzees living in a rain forest of Côte d’Ivoire. J Infect Dis 179 : S120–S126. [Google Scholar]
  7. Formenty P, Hatz C, LeGuenno B, Stoll A, Rogenmoser P, Widmer A, 1999. Human infection due to Ebola virus, subtype Côte d’Ivoire: clinical and biologic presentation. J Infect Dis 179 : S48–S53. [Google Scholar]
  8. Amblard J, Obiang P, Prechaud C, Bouloy M, LeGuenno B, 1997. Identification of the Ebola virus in Gabon in 1994. Lancet 349 : 181–182. [Google Scholar]
  9. Georges AJ, Leroy EM, Renaut AA, Benissan CT, Nabias RJ, Ngoc MT, Obiang PI, Lepage JP, Bertherat EJ, Benoni DD, Wickings EJ, Amblard JP, Lansoud-Soukate JM, Milleliri JM, Baize S, Georges-Courbot MC, 1999. Ebola hemorrhagic fever outbreaks in Gabon, 1994–1997: epidemiologic and health control issues. J Infect Dis 179 : S65–S75. [Google Scholar]
  10. Muyembe-Tamfum JJ, Kipasa M, 1995. Ebola hemorrhagic fever in Kikwit, Zaire. Lancet 345 : 1448. [Google Scholar]
  11. Centers for Disease Control and Prevention, 2001. Outbreak of Ebola hemorrhagic fever-Uganda, August 2000-January 2001. MMWR Morb Mortal Wkly Rep 50 : 73–77. [Google Scholar]
  12. World Health Organization, 2001. Outbreak of Ebola haemorrhagic fever, Uganda, August 2000-January 2001. Wkly Epidemiol Rec 76 : 41–46. [Google Scholar]
  13. World Health Organization, 2003. Outbreak(s) of Ebola haemorrhagic fever, Congo and Gabon, October 2001–July 2002. Wkly Epidemiol Rec 78 : 217–224. [Google Scholar]
  14. Leroy EM, Rouquet P, Formenty P, Souquière S, Kilbourne A, Froment J-M, Bermejo M, Smit S, Karesh W, Swanepoel R, Zaki SR, Rollin PE, 2004. Multiple Ebola virus transmission events and rapid decline of Central African wildlife. Science 303 : 387–390. [Google Scholar]
  15. World Health Organization, 2003. Outbreak(s) of Ebola haemorrhagic fever in the Republic of Congo, January–April 2003. Wkly Epidemiol Rec 78 : 285–296. [Google Scholar]
  16. Walsh PD, Abernethy KA, Bermejo M, Beyers R, de Wachter P, Akou ME, Huijbregts B, Mambounga DI, Toham AK, Kilbourn AM, Lahm SA, Latour S, Maisels F, Mbina C, Mihindou Y, Obiang SN, Effa EN, Starkey MP, Telfer P, Thibault M, Tutin CE, White LJ, Wilkie DS, 2003. Catastrophic ape decline in western equatorial Africa. Nature 422 : 611–614. [Google Scholar]
  17. Arata AA, Johnson B, 1978. Approaches towards studies on potential reservoir of viral haemorrhagic fever in southern Sudan (1977). Pattyn SR, ed. Ebola Virus Haemorrhagic Fever. Proceedings of an International Colloquium on Ebola Virus Infection and Other Haemorrhagic Fevers. Antwerp, Belgium, December 6–8, 1977. Amsterdam: Elsevier/North-Holland Biomedical Press, 191–202.
  18. Germain M, 1978. Collection of mammals and arthropods during the epidemic of haemorrhagic fever in Zaie. Pattyn SR, ed. Ebola Virus Haemorrhagic Fever. Proceedings of an International Colloquium on Ebola Virus Infection and Other Haemorrhagic Fevers. Antwerp, Belgium, December 6–8, 1977. Amsterdam: Elsevier/North-Holland Biomedical Press, 185–189.
  19. Reiter P, Turell M, Coleman R, Miller B, Maupin G, Liz J, Kuehne A, Barth J, Geisbert J, Dohm D, Glick J, Pecor J, Robbins R, Jahrling P, Peters C, Ksiazek T, 1999. Field investigations of an outbreak of Ebola Hemorrhagic fever, Kikwit, Democratic Republic of the Congo: arthropod studies. J Infect Dis 179 : S148–S154. [Google Scholar]
  20. Leirs H, Mills JN, Krebs JW, Childs JE, Akaibe D, Woollen N, Ludwig G, Peters CJ, Ksiazek TG, 1999. Search for the Ebola virus reservoir in Kikwit, Democratic Republic of the Congo: reflections on a vertebrate collection. J Infect Dis 179 : S155–S163. [Google Scholar]
  21. Breman JG, Johnson KM, van der Groen G, Robbins CB, Szczeniowski MV, Ruti K, Webb PA, Meier F, Heymann DL, 1999. A search for Ebola virus in animals in the Democratic Republic of the Congo and Cameroon: ecologic, virologic, and serologic surveys, 1979–1980. J Infect Dis 179 : S139–S147. [Google Scholar]
  22. Johnson BK, Wambui C, Ocheng D, Gichogo A, Oogo S, Libondo D, Gitau LG, Tukei PM, Johnson ED, 1986. Seasonal variation in antibodies against Ebola virus in Kenyan fever patients (letter). Lancet 8490 : 1160. [Google Scholar]
  23. Monath TP, 1999. Ecology of Marburg and Ebola viruses: speculations and directions for future research. J Infect Dis 179 : S127–S138. [Google Scholar]
  24. Tucker CJ, Wilson JM, Mahoney R, Anyamba A, Linthicum K, Myers MF, 2002. Climatic and ecological context of the 1994–1996 Ebola outbreaks. Photogrammetric Eng Remote Sens 68 : 174–152. [Google Scholar]
  25. Wilson JM, Tucker CJ, 2002. Use of remote sensing in epidemic surveillance and response. World Meteorol Organ Bull 51 : 136–139. [Google Scholar]
  26. Cracknell, AP, 1997. The Advanced Very High Resolution Radiometer. London: Taylor and Francis, 534.
  27. Kidwell KB, 1997. NOAA Polar Orbiter Users Guide. Rockville, MD: National Oceanic and Atmospheric Administration.
  28. Pinzon JE, Brown ME, Tucker CJ, 2004. Satellite time series correction of orbital drift artifacts using empirical mode decomposition. Huang NE, Shen SSP, eds. EMD and Its Applications. Singapore: World Scientific 10: 285–295.
  29. Pinzon JE, 2002. Using HHT to successfully uncouple seasonal and interannual components in remotely sensed data. SCI 2002 Proceedings. Orlando, FL. July 14–18, 2002.
  30. Lotsch A, Friedl MA, Pinzon JE, 2003. Spatio-temporal deconvolution of NDVI image sequences using independent component analysis. IEEE Trans Geosci Remote Sens 41 : 2938–2942. [Google Scholar]
  31. Tucker CJ, 1979. Red and photographic infrared linear combinations for monitoring vegetation. Remote Sens Environ 8 : 127–150. [Google Scholar]
  32. Myneni RB, Hall FG, Sellers PJ, Marshak AL, 1995. The interpretation of spectral vegetation indexes. IEEE Trans Geosci Remote Sensing 33 : 481–486. [Google Scholar]
  33. Tucker CJ, Sellers PJ, 1986. Satellite remote sensing of primary production. Int J Remote Sens 7 : 1395–1416. [Google Scholar]
  34. Justice CO, Holben BN, Gwynne MD, 1986. Monitoring East African vegetation using AVHRR data. Int J Remote Sens 7 : 1453–1474. [Google Scholar]
  35. Nicholson SE, Davenport ML, Malo AR, 1990. A comparison of vegetation response to rainfall in the Sahel and east Africa using Normalized Difference Vegetation Index from NOAA-AVHRR. Climate Change 17 : 209–241. [Google Scholar]
  36. Cihlar J, St. Laurent L, Dyer JA, 1991. The relation between Normalized Difference Vegetation Index and ecological variables. Remote Sens Environ 35 : 279–298. [Google Scholar]
  37. Linthicum KJ, Anyamba A, Tucker CJ, Kelley PW, Myers MF, Peters CJ, 1999. Climate and satellite indicators to forecast Rift Valley fever epidemics in Kenya. Science 285 : 397–400. [Google Scholar]
  38. Linthicum KJ, Bailey CL, Davies FG, Tucker CJ, 1987. Detection of Rift Valley fever viral activity in Kenya by satellite remote sensing imagery. Science 235 : 1656–1659. [Google Scholar]
  39. Betherton CS, Smith C, Wallace JM, 1992. An intercomparison of methods for finding coupled patterns in climate data. J Climate 5 : 541–560. [Google Scholar]
  40. Wallace JM, Smith C, Bretherton CS, 1992. Singular value decomposition of winter time sea surface temperature and 500-mb height anomalies. J Climate 5 : 561–576. [Google Scholar]
  41. Cherry S, 1996. Singular value decomposition analysis and canonical correlation analysis. J Climate 9 : 2003–2009. [Google Scholar]
  42. Vermote EF, El Saleous NZ, Kaufman YF, Dutton E, 1997. Data pre-processing: stratospheric aerosol perturbing effect on the remote sensing of vegetation: correction method for the composite NDVI after the Pinatubo eruption. Remote Sens Rev 15 : 7–21. [Google Scholar]
  43. Hansen J, Lacis A, Ruedy R, Sato M, 1992. Potential climate impact of Mount Pinatubo eruption. Geophys Res Lett 19 : 215–218. [Google Scholar]
  44. Wright SJ, 1996. Phenological responses to seasonality in tropical forest plants. Mulkey SS, Chazdon RL, Smith AP, eds. Tropical Forest Plant Ecophysiology. New York: Chapman & Hall/International Thomson Publishing Company, 450–455.
  45. Emmons LH, 1980. Ecology and resource partitioning among nine species of African rain forest squirrels. Ecol Monogr 50 : 31–54. [Google Scholar]
  46. Gautier-Hion A, 1980. Seasonal variations of diet related to species and sex in a community of Cercopithecus monkeys. J Anim Ecol 49 : 237–269. [Google Scholar]
  47. Gautier-Hion A, Michaloud G, 1989. Are figs always keystone resources for tropical frugivorous vertebrates? A test in Gabon. Ecology 70 : 1826–1833. [Google Scholar]

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  • Received : 09 Feb 2004
  • Accepted : 24 Apr 2004

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