Future Risk Assessments for the Impact of Climate Change on Vector-Borne Viruses of Livestock: Potential of Genomics, Transcriptomics and Proteomics Approaches – A Review

Abstract

Climate and habitat change, together with globalisation, are important factors in the emergence of arthropodborne viruses (arboviruses). Changes in the range and abundance of the virus, vectors and hosts may create new combinations of host-pathogen-vector interactions for which data are not available. This paper reviews the genomics data currently available for arboviruses, their vectors and hosts, and assesses the level of understanding of the genetic factors affecting their adaptation to climate. It is anticipated here that genomics, transcriptomics and proteomics approaches may enable the breakdown of the traditional risk assessment pathways into the individual biochemical steps for each of the three interfaces between the virus, vector and host such that future risk assessments could be based on looking for certain gene combinations and their resulting expression profiles. Differences in the virus interaction with the arthropod midgut have been implicated in specifically affecting the extrinsic incubation period for some arboviruses, while differences in viral replication and dissemination through the arthropod may affect vector competence for other arboviruses. Genomics approaches to identify the proteins involved will enhance our understanding of vector competence and may explain why some arbovirus genotypes are more efficiently replicated in the vector at elevated temperatures. Such studies may also reflect the diversity present in real-world systems to a greater extent than experimental systems involving a single combination of vector and virus genotypes. Understanding the genetic basis for tissue tropism will facilitate prediction of new routes of transmission.