Influence of climate change on diseases of wild animals

Summary

The occurrence of transferable diseases in wild animals generally reflects the causative agent’s distribution. The influence of climate change on the prevalence of pathogenic organisms is either exerted directly by causative agents with an increased survival rate as related to higher average annual temperatures, or indirectly because vectors (e.g. ticks, mosquitoes) experience better environmental conditions similarly promoting their viability and allowing them to invade new areas of circulation. The latter option explains why pathogen-carrying vectors such as ticks and mosquitoes prevail at higher sea levels than observed two decades ago. In recent years, vectors with seasonal cycles show longer periods of incidence. In addition, parasitic eggs, larvae and parasitic organisms at intermediate stages can be found at higher sea levels as they too benefit from changing climate conditions. For this reason cumulative purulent and abscess forming pneumonia is observed in chamois which originate from lungworm infections. This contribution demonstrates the relationship between climate factors and transferable diseases. The geographical dissemination and incidence of many diseases interferes with environmental changes. Additionally, risk factors increasing the diseases’ prevalence and incidence are discussed. Finally, selected examples of our own findings on the impact of climate changes on diseases (tularaemia) and on habitats of alpine wild animal species (black grouse, snow grouse, chamois and ibex) are highlighted.