Migratory Birds, Ticks, and Crimean-Congo Hemorrhagic Fever Virus

摘要

To the Editor: In a recently published study, Estrada-Pe.a et al. reported the fi nding of Crimean-Congo hemorrhagic fever virus (CCHFV) in adult Hyalomma lusitanicum ticks from red deer (Cervus elaphus) in Spain during 2010 (1). Phylogenetic analysis showed that the virus was most likely of African origin. Here, we present a model for the transfer of CCHFV-infected ticks by migratory birds from Africa to Europe.CCHFV is an RNA virus in the genus Nairovirus, family Bunyaviridae. It is transmitted to humans through tick bites or by contact with blood or tissues from infected ticks, livestock, or humans. Manifestations of severe cases are internal and external hemorrhages and multiorgan failure; the case-fatality rate is ≈30% (2,3). CCHFV has the widest geographic distribution of any tick-borne virus, encompassing ≈30 countries from eastern China through Asia, the Middle East, and southeastern Europe to Africa (3,4). During the past decade, the virus has emerged in new areas of Europe, Africa, the Middle East, and Asia and has increased in disease-endemic areas (5) (online Technical Appendix, wwwnc.cdc.gov/EID/pdfs/12-0718-Techapp.pdf).