Global ecological niche modelling of current and future distribution of peste des petits ruminants virus (PPRv) with an ensemble modelling algorithm.

Abstract

Peste des petits ruminants (PPR) is a highly contagious transboundary viral disease of sheep and goats that negatively impacted the farmers and pastoralists' livelihood in Africa and Asia. To overcome the disease's consequences, the OIE and FAO are collaborating efforts to eradicate the disease once and for all. We developed a predictive model that delineates suitable territories for the virus globally in support of this eradication programme. To achieve this, we used an ecological niche modelling with an ensemble algorithm. AUC-ROC curve, true skill statistics (TSS) and Kappa values were used to evaluate the model's performance. A TSS value greater than 0.7 was used to pool outputs of the nine model. The ensemble model has better performance than individual models by every evaluation metrics (Kappa=0.82, TSS=0.88 and ROC=0.99). Annual minimum temperature (24.92%), annual maximum temperature (21.37%), goat density (18.03%) and solar radiation (14.04%) have the highest overall contribution in the ensemble model. The model indicates that India, Mongolia, Iraq, Iran, Afghanistan, Nepal, Tanzania, Uganda, Kenya, Sudan, Angola, Nigeria, DRC, Ghana, Sierra Leon, Southern Spain, France, Albania, Montenegro, Macedonia, Italy, Armenia and Azerbaijan are highly suitable for PPRv. In 2040, suitable territories for PPRv will diminish, indicating the odds are with us in eradicating disease by 2030. We believe that this model can be used as an epidemiological tool to facilitate the global eradication programme of the disease set by the OIE and FAO.