Andersen et al.
Continued expansion of tick-borne pathogens: Tick-borne encephalitis complex and Anaplasma phagocytophilum in Denmark.
Ticks Tick Borne Dis. 2018, in press, doi.org/10.1016/j.ttbis.2018.09.007

In Denmark, TBE was first reported in the late 1950s on the island of Bornholm and for the next five decades, Bornholm was thought to represent an isolated TBE focus. However, human cases have been reported in other parts of Denmark, e.g. north Zealand. The authors have carried out a large-scale seroprevalence study for TBE and Louping Ill virus (LIV) (which is at least co-existing with TBE on the island of Bornholm) as sentinel and determined the prevalence for Anaplasma phagocytophilum in roe deer. TBE neutralizing antibodies could be detected along the coast of all major islands and mainland Denmark. Compared to a previous study in 2002/2003, new TBE foci could be identified with 6.9% TBE positive samples during the hunting season between 2013 and 2014, (geographic expansion mainly in northern, central and western Jutland, south-eastern part of Funen and Lolland and Falster). LIV foci were confirmed on the island of Bornholm and also in north Zealand. In a selected group of roe deer, an overall prevalence of 94% for A. phagocytophilum was found. This was a doubling compared to 2002 and may indicate an expansion of this pathogen in Denmark. However, it should be mentioned that different strains of A. phagocytophilium infect roe deer and humans and which can cause human granulocytic anaplasmosis.

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