Ziegler et al.
West Nile virus epizootic in Germany, 2018
Antivir. Res. 2019; 162: 39-43
The unusual climatic conditions in Europe in 2018 enabled some exotic arthropods to undergo development from larval and nymphal stage to adult stages, e.g. the tick genus Hyalomma has been detected in Germany (see Snapshot 35/2018) and some of these ticks were infected with Rickettsia aeschlimannii, which is uncommon in Central Europe. In addition, in October 2018, a Hyalomma marginatum tick has been found in Austria (Eurosurveillance 23 (48), Nov. 29, 2018). So far, no Crimean-Congo hemorrhagic fever transmitted by Hyalomma ticks has been reported in Central Europe but has been notified in Kosovo and in Spain (Ahmeti, Emerg. Infect. Dis, 2019, Feb., in press).
In August and September 2018, six fatal cases of West Nile virus (WNV) among wild and captive birds have been observed in Germany. In addition, more WNV antibody positive birds have been detected. Phylogenetic analyses indicate that this virus strain is very similar with strains found in the Czech Republic. These observations show that the expansion and propagation of the arthropod-borne WNV in southern and southeastern European countries continues and has reached Central Europe, Germany.
Migratory birds are involved in the transmission of emerging arbo-pathogens in Central Europe. With longer periods of high temperatures and relatively mild winters, conditions are provided for the incursion and establishment of exotic pathogens transmitted by immigrating ticks and mosquitos.