Uchida et. al.
Survey of tick-borne zoonotic viruses in wild deer in Hokkaido, Japan
J. Vet. Med. Sci., in press
While the first human case of TBE has been diagnosed on the island of Hokkaido, Japan, in 1993, there was a long period with no further occurrences reported until 2016 and 2017, when three new cases of TBE were registered. A seroepidemiological study in wild deer (Cervus nippon yesoensis) was carried out between 2011 and 2016 at three places in Hokkaido – in the north, the east and in the south of the island. Sera were analyzed by ELISA and neutralization test (NT) for TBE (and JEV). A total of five sera collected from deer in the northern part of Hokkaido (Toyotomi) were found NT-positive for TBE (but negative for JEV). In northern areas of Hokkaido, no human cases have so far been reported. However, as some deer may migrate up to 100 km, it cannot be ruled out that TBE foci are located outside of Toyotomi.