Transstadial and transovarial persistence ofBabesia divergensDNA inIxodes ricinusticks fed on infected blood in a new skin-feeding technique

Abstract

Although Babesia divergens is the the principal confirmed zoonotic Babesia sp. in Europe, there are gaps in our knowledge of its biology and transmission by the tick Ixodes ricinus. In order to reproduce the part of the parasite cycle that occurs in the vector, an in vitro animal skin feeding technique on blood containing in vitro cultivated B. divergens was developed. Parasite DNA was detected in all samples of salivary glands of nymphs and adults that had fed on parasitized blood as larvae and nymphs, respectively, indicating acquisition as well as a transtadial persistence of B. divergens. PCR performed on eggs and larvae produced by females that had fed on parasitized blood demonstrated the existence of a transovarial transmission of the parasite. Gorging B. divergens infected larvae on non-infected gerbils showed persistance of the parasite over moulting into the resulting nymphs. These results indicate that the parasitic stages infective for the vector (i.e. the sexual stages) can be produced in vitro. To our knowledge, this is the first report of artificial feeding of I. ricinus via membrane as well as in vitro transmission of B. divergens to its vector. The opportunities offered by the use of such a transmission model of a pathogen by I. ricinus are discussed.

Transmission ofBartonella henselaebyIxodes ricinus

“…The method of artifi cial feeding used in this study was adapted from the method of Bonnet et al (33). Ticks were placed in 75-cm 2 tissue culture fl asks pierced at the top to accommodate a 4-cm diameter glass feeder.…”

“…Second blood meal on uninfected blood meal (partial feeding during 84 h) a gerbil or rabbit skin membrane at the bottom. Gerbil skins were used for feeding larvae and rabbit skins for feeding nymphs and adults (33). To attract ticks, a constant temperature (37°C) was maintained by a water-jacket circulation system through the glass feeder.…”

The first detection of species of Babesia Starcovici, 1893 in moose, Alces alces (Linnaeus), in Norway

“…Humans can serve as accidental hosts for numerous species of Babesia (see Yabslei and Shock 2013). Transovarial transmission of some Babesia spp has been documented in Ixodes ricinus (see Bonnet et al 2007bBonnet et al , 2009.…”

Babesia behnkei sp. nov., a novel Babesia species infecting isolated populations of Wagner¿s gerbil, Dipodillus dasyurus, from the Sinai Mountains, Egypt

“…The primers and thermal profiles used in this study have been described previously [7,10,[47][48][49][50]. Reactions were performed in 1× PCR buffer, 1 U Taq polymerase, 1 μM of each primer and 2-5 μl of the extracted DNA sample.…”

“…Primers GF (5'-G(C/T) (C/T)T TGT AAT TGG AAT GAT GG-3') and GR (5'-CCA AAG ACT TTG ATT TCT CTC-3') were used for the detection of Babesia/ Theileria spp. by the amplification of a 559 bp fragment of the 18S rDNA [48,49]. Primers Nbab_1F (5'-AGC CAT GCA TGT CTA AGT ATA AGC TTT T-3') [10] and TB Rev (5'-AAT AAT TCA CCG GAT CAC TCG-3') [50] were used for the genetic characterization of positive isolates by the amplification of a 1,700 bp near-full-length sequence of the 18S rRNA gene.…”