The Expanding Threat of Crimean-Congo Haemorrhagic Fever Virus: Role of Migratory Birds and Climate Change as Drivers of Hyalomma spp. Dispersal in Europe

The Crimean-Congo Haemorrhagic Fever Virus (CCHFV) is an emerging zoonotic pathogen with a high case fatality risk. Its primary vectors, Hyalomma spp. ticks, are expanding their geographic range, raising concerns about the increasing risk of Crimean-Congo Haemorrhagic Fever (CCHF) outbreaks in Europe. Migratory birds contribute considerably to the spread of Hyalomma ticks, transporting immature forms over long distances during spring migrations. Additionally, climate change plays a crucial role in this expansion by creating favorable conditions for Hyalomma spp. survival and dispersal. This review explores the interplay between Hyalomma spp. ecology as vectors of CCHFV, the role of migratory birds and the impact of climate change on the dispersal of CCHFV across Europe. Understanding these dynamics is essential for assessing future risks, improving surveillance strategies, and implementing effective public health interventions.