Molecular survey of Ehrlichia infection in ticks from animals in Yamaguchi Prefecture, Japan.

A total of 82 ticks collected from wild animals and dogs in Yamaguchi Prefecture, Japan were examined for Ehrlichia infection by using polymerase chain reaction (PCR) primers that amplify DNA of most members of the genus Ehrlichia. A DNA sample from an Ixodes ovatus nymph from a bear in Yamaguchi Prefecture, Japan, was positive in the screening PCR. Subsequent PCR using two sets of primers yielded a 1431 bp segment of the 16S rRNA gene and the sequence was very similar to those of E. chaffeensis and E. muris, and a strain variant of a recently described Ehrlichia species isolated from I. ovatus in other prefectures of Japan.