Stoefs et al.
Autochthonous cases of tick-borne encephalitis, Belgium, 2020
Emerg. Infect. Dis. 2021, in press, doi.org/10.3201/eid2708.211175
In Belgium, seroprevalence studies in various animals indicate that TBE virus is endemic in this country. However, no autochthonous human case has so far been reported. This has now changed: three autochthonous TBE virus infections acquired in Belgium (patients living in western, northern, and central Belgium) in 2020 have been described.
Three individuals aged 48, 58 and 59 years old became infected after tick bites in various regions of Belgium. The patients had relatively mild to severe symptoms. TBE was serologically diagnosed by TBE IgM and IgG ELISA and immunofluorescence assay, and infection was confirmed by neutralization assay. In one case, TBE infection was confirmed by detection of TBE virus RNA in an acute-phase serum sample.
Flagging of ticks and studies on the prevalence of TBE virus is planned for this year in regions where exposure most likely occurred.