1. Epidemiology and Global Health
  2. Microbiology and Infectious Disease
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Updates to the zoonotic niche map of Ebola virus disease in Africa

  1. David M Pigott  Is a corresponding author
  2. Anoushka I Millear
  3. Lucas Earl
  4. Chloe Morozoff  Is a corresponding author
  5. Barbara A Han
  6. Freya M Shearer
  7. Daniel J Weiss
  8. Oliver J Brady
  9. Moritz UG Kraemer
  10. Catherine L Moyes
  11. Samir Bhatt
  12. Peter W Gething
  13. Nick Golding
  14. Simon I Hay
  1. University of Washington, United States
  2. Li Ka Shing Centre for Health Information and Discovery, United Kingdom
  3. Cary Institute of Ecosystem Studies, United States
  4. University of Oxford, United Kingdom
  5. University of Melbourne, Australia
Research Advance
Cite this article as: eLife 2016;5:e16412 doi: 10.7554/eLife.16412
3 figures, 3 tables and 1 data set

Figures

Updated Ebola virus disease occurrence database.

Human index cases are represented by red circles, animal occurrences in blue. New occurrence information is indicated by the black circle. The coordinates of polygon centroids are displayed for occurrences defined by an area greater than 5 km x 5 km.

https://doi.org/10.7554/eLife.16412.002
Figure 2 with 3 supplements
Combined suitability surfaces for each of the potential reservoir bat groupings.

For each layer the species specific suitability maps were combined to produce a surface approximating the probability that any bat species in that group may be present. Regions in blue (1) are most environmentally similar to locations reporting bat records. Areas in yellow (0) are the least environmentally similar. The top left panel depicts Group 1, top right Group 2 and bottom left Group 3 bats.

https://doi.org/10.7554/eLife.16412.003
Figure 2—figure supplement 1
Group 1 bat distributions.

The environmental suitability for each of the three bat species in Group 1 are displayed. Regions in dark blue (1) are most environmentally similar to locations reporting bat records. Areas in white (0) are the least environmentally similar. The black outline depicts the expert opinion range maps as determined by the International Union for the Conservation of Nature (Schipper et al., 2008) and the black dots represent occurrence records reported by the Global Biodiversity Information Facility (www.gbif.org/) and from published peer-reviewed articles. From top left, clockwise: Epomops franqueti, Hypsignathus monstrosus, summary Group 1 layer combining all three maps, and Myonycteris torquata.

https://doi.org/10.7554/eLife.16412.004
Figure 2—figure supplement 2
Group 2 bat distributions.

The environmental suitability for each of the five bat species in Group 2 are displayed. Regions in dark blue (1) are most environmentally similar to locations reporting bat records. Areas in white (0) are the least environmentally similar. The black outline depicts the expert opinion range maps as determined by the International Union for the Conservation of Nature (Schipper et al., 2008) and the black dots represent occurrence records reported by the Global Biodiversity Information Facility (www.gbif.org/). From top left, clockwise: Tadarida condylura, Rousettus aegyptiacus, Miniopterus pusillus, summary Group 2 layer combining all five maps, Eidolon helvum, and Epomophorus gambianus.

https://doi.org/10.7554/eLife.16412.005
Figure 2—figure supplement 3
Group 3 bat distributions.

The environmental suitability for each of the seven bat species in Group 3 are displayed. Regions in dark blue (1) are most environmentally similar to locations reporting bat records. Areas in white (0) are the least environmentally similar. The black outline depicts the expert opinion range maps as determined by the International Union for the Conservation of Nature (Schipper et al., 2008) and the black dots represent occurrence records reported by the Global Biodiversity Information Facility (www.gbif.org/). From top left, clockwise: Epomops buettikoferi, Miniopterus schreibersii, Epomophorus labiatus, Miniopterus inflatus, summary Group 3 layer combining all seven maps, Otomops martiensseni, Hipposideros gigas, and Rhinolophus eloquens.

https://doi.org/10.7554/eLife.16412.006
Figure 3 with 2 supplements
Updated map showing areas most environmentally suitable for the zoonotic transmission of Ebola virus.

Areas closer to dark red (1) are most environmentally similar to locations reporting Ebola virus occurrences; areas in light yellow (0) are least similar. Countries with borders outlined are those which are predicted to contain at-risk areas for zoonotic transmission based on a thresholding approach. Output displayed generated from model using the three consolidated bat covariates.

https://doi.org/10.7554/eLife.16412.007
Figure 3—figure supplement 1
Absolute differences between previous and revised maps.

Generated by subtracting the original eLife publication pixel probabilities from the newly generated values and restricted to those areas determined to be at-risk. Areas in yellow are essentially consistent. Areas in purple have probability values greater than the previous output; areas in green have probability values lower than previous outputs.

https://doi.org/10.7554/eLife.16412.008
Figure 3—figure supplement 2
Zoonotic niche map based upon inclusion of individual bat covariate layers.

Areas closer to dark red (1) are most environmentally similar to locations reporting Ebola virus occurrences; areas in light yellow (0) are least similar. Countries with borders outlined are those which are predicted to contain at-risk areas for zoonotic transmission based on a thresholding approach. Output displayed generated from model using individual bat covariate layers.

https://doi.org/10.7554/eLife.16412.009

Tables

Table 1

National populations at risk.

https://doi.org/10.7554/eLife.16412.010
CountryPopulation-at-risk (in 100,000s)
Countries previously
reporting index cases
Democratic Republic of the Congo170.18
Uganda21.58
Guinea17.61
Côte d’Ivoire4.08
Gabon3.65
South Sudan1.80
Republic of Congo1.07
Countries with no
reported index cases
Nigeria29.13
Cameroon22.90
Central African Republic7.62
Liberia5.88
Ghana4.04
Sierra Leone3.94
Angola3.25
Togo1.78
Ethiopia1.75
Equatorial Guinea1.22
Tanzania1.18
Burundi1.07
Mozambique0.55
Madagascar<0.1
Kenya<0.1
Malawi<0.1
Table 2

Comparison of previous and revised niche models.

https://doi.org/10.7554/eLife.16412.011
Revised niche map (with summary bat layers)Revised niche map (with individual bat layers)Previous eLife niche map (Pigott et al., 2014)
AUC0.8236 ± 0.080.8195 ± 0.080.85 ± 0.04
Occurrencesn = 57 (animals), n = 31 (humans)n = 57 (animals), n = 31 (humans)n = 51 (animals), n = 30 (humans)
Ranked relative contributionsEVI mean (0.55)EVI mean (0.46)EVI mean (0.65)
Group 1 bat distribution (0.18)Hypsignathus monstrosus (0.15)Elevation (0.12)
LST mean (night) (0.08)Epomops franqueti (0.08)LST mean (night) (0.08)
Elevation (0.06)Otomops martiensseni (0.06)PET mean (0.06)
LST mean (day) (0.04)Epomophorus labiatus (0.04)Bat distribution (0.04)
Table 3

Final bats included in analysis classified by evidence grouping.

https://doi.org/10.7554/eLife.16412.012
GroupingBatOccurrences
Group 1Franquet’s epauletted fruit bat
(Epomops franqueti)
442
Hammerheaded fruit bat
(Hypsignathus monstrosus)
254
Little collared fruit bat
(Myonycteris torquata)
107
Group 2Angolan free-tailed bat
(Tadarida condylura, formerly Mops condylurus)
179
Egyptian fruit bat
(Rousettus aegyptiacus)
177
Gambian epauletted fruit bat
(Epomophorus gambianus)
166
Peter’s dwarf epauletted fruit bat
(Micropteropus pusillus)
208
Straw-coloured fruit bat
(Eidolon helvum)
282
Group 3Buettikofer’s epauletted fruit bat
(Epomops buettikoferi)
50
Common bent-wing bat
(Miniopterus schreibersii)
31
Eloquent horseshoe bat
(Rhinolophus eloquens)
61
Ethiopian epauletted fruit bat
(Epomophorus labiatus)
187
Giant leaf-nosed bat
(Hipposideros gigas)
21
Greater long-fingered bat
(Miniopterus inflatus)
56
Large-eared free-tailed bat
(Otomops martiensseni)
33

Data availability

The following data sets were generated
  1. 1

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