West Nile Virus in Germany: An Emerging Infection and Its Relevance for Transfusion Safety

West Nile virus (WNV) is an arthropod-borne virus (arbovirus). It circulates in an enzootic cycle between ornithophilic mosquitoes as vectors and reservoirs and avian host species for amplification, but humans can be infected as accidental hosts. In most individuals, WNV infection remains silent, while 20% develop mild symptoms of West Nile fever, and only 1% develop neuroinvasive disease (WNND). Human WNV cases have been identified in Southern and Eastern Europe for more than 20 years, but until 2018, Germany was considered to be a non-endemic country. This changed when in the exceptionally warm summer of 2018, conditions for viral replication in mosquitoes were ideal, and the first WNV cases among birds and horses were identified. The widespread domesticCulexmosquitoes are efficient vectors for WNV. Autochthonous mosquito-borne WNV infections in humans were reported in all following years, indicating a continuous circulation in the affected areas of Central-East Germany. So far, no clear expansion of the affected areas is discernible but may develop. WNV is a transfusion-transmissible-infection, and donor deferral or testing of donations after a stay in an affected area are effective means to ensure transfusion safety. WNV transmissions via blood products often result in WNND due to the predisposing underlying medical conditions of transfusion recipients. From 2020 onwards, roughly 80% of all blood establishments in Germany tested their donations for WNV using nucleic acid ...
Source: Transfusion Medicine and Hemotherapy - Category: Hematology Source Type: research