Agergaard et al.
New tick-borne encephalitis virus hot spot in Northern Zealand, Denmark, October 2019
Eurosurveillance 2019, 24 (43):pi=1900639, doi.org/10.2807/1560-7917.ES.2019.24-43.1900639
In Denmark, TBE has so far only been reported from the island of Bornholm, from Northern Zealand (in the forest of Tokkekøb Hegn), from the island of Funen and recently from Jutland (see Snapshot week 35/2019).
Three new TBE cases, which have occurred this summer, have been reported from Northern Zealand in the forest of Tisvilde Hegn. (Tisvilde Hegn is Denmark’s fifth largest forest stretching from the coast in Tisvildeje to Aserbo plantation. The forest is located directly beside the Kattegat and has a coastline stretching 8 km). Ticks were collected in this forest area and TBE virus could be detected (by RT-qPCR) in Ixodes ricinus nymphs. Metagenomic whole genome sequencing was carried out and showed that all isolates from this forest were genetically identical and were closely related to a TBE virus strain from Mandel, Norway.
In contrast, the TBE virus sequence from Tokkekøb Hegn (which is about 40 km away from Tisvilde Hegn) grouped with TBE virus strains from Sweden. The authors concluded that the TBE virus strain found in Tokkekøb Hegn may have been imported by migrating birds from Norway. In order to reduce the risk for visitors, some protective measures were carried out at the site of the TBE virus micro-focus like fencing, grass cutting and signage along the site.