Epidemiological Survey of Babesia Species in Japan Performed with Specimens from Ticks Collected from Dogs and Detection of New Babesia DNA Closely Related to Babesia odocoilei and Babesia divergens DNA

Abstract

Detection and analysis of Babesia species from ticks recovered from dogs in Japan were attempted by PCR and nucleotide sequence analysis based on the 18S rRNA gene, respectively. A total of 1,136 ticks were examined for Babesia DNA by 18S rRNA-based PCR and nucleotide sequencing. Partial sequences of Babesia canis vogeli DNA were detected from six ticks in Aomori, Nara, Hiroshima, Oita, and Okinawa Prefectures; and Babesia gibsoni Asia-1 DNA was also detected in four ticks in Osaka, Hiroshima, Miyazaki, and Okinawa Prefectures. Unique sequences of 1,678 bp were also obtained from Ixodes ovatus ticks in Akita and Fukui Prefectures. The sequences were similar to those of Babesia odocoilei (97.7%) and Babesia divergens (97.6%). This is the first report of the detection of DNA belonging to this group in Japan.Animals are often exposed to a large number of tick species, depending upon the distribution of these arthropod vectors in the environment. Recently, interest in ticks of domestic animals has been increasing because of emerging and reemerging tick-borne diseases, including those caused by rickettsial, bacterial, and protozoal pathogens, and their zoonotic nature. Ixodid tick species from canine hosts in Japan were documented in a recent report (19). The tick species of canine hosts in Japan showed more variation than the tick species of canine hosts in European countries. Haemaphysalis longicornis was the species most frequently found. This was followed by Hamaphysalis flava, Rhipicephalus sanguineus, and Ixodes ovatus as the next most dominant tick species. As dogs are in close contact with humans,

Molecular Evidence of Infections withBabesia gibsoniParasites in Japan and Evaluation of the Diagnostic Potential of a Loop-Mediated Isothermal Amplification Method

“…The cases of canine babesiosis reported in Okinawa Prefecture have been considered to be caused by B. gibsoni and B. canis (21). Recently, B. gibsoni and B. canis DNAs were detected by PCR from ticks in Aomori and Okinawa Prefectures (11). However, in this study, all positive dogs had B. gibsoni infection and B. canis infection was not seen.…”

Incidence of Canine Babesia gibsoni Infection and Subclinical Infection among Tosa dogs in Aomori Prefecture, Japan

“…Furthermore, natural infection with this pathogen, as identified by PCR assays, has been found only in dogs of the Tosa breed, and has not been identified in tests of 872 dogs of other breeds in dogs of any other breeds in Aomori Prefecture [11]. It has been reported in 2003, that B. gibsoni parasite was not detected in ticks from eastern Japan, including Aomori Prefecture, in an epidemiological survey [12]. In the light of these data, our findings suggest the possibility that B. gibsoni in Tosa dogs might be transmitted through blood contamination during dog fighting, rather than through ticks.…”

A Possible Treatment Strategy and Clinical Factors to Estimate the Treatment Response in Bebesia gibsoni Infection

“…Canine babesiosis is a tick-borne disease in dogs and both Babesia gibsoni and B. canis are seen in dogs in Japan [1,2,11,12]. B. gibsoni infected dogs are generally seen in the west of Japan and dogs affected by B. canis are mainly observed on Okinawa island.…”