Grigoreva, Y. E. | Search bioRxiv

bioRxiv2020

Rhipicephalus microplus and its vector-borne haemoparasites in Guinea: further species expansion in West Africa

AO_SCPLOWBSTRACTC_SCPLOWRhipicephalus microplus is an ixodid tick with a pantropical distribution that represents a serious threat to livestock. West Africa was free of this tick until 2007, when its introduction into Benin was reported. Shortly thereafter, the further invasion of this tick into West African countries was demonstrated. In this paper, we describe the first detection of R. microplus in Guinea and list the vector-borne haemoparasites that were detected in the invader and indigenous Boophilus species. In 2018, we conducted a small-scale survey of ticks infesting cattle in three administrative regions of Guinea: N`Zerekore, Faranah, and Kankan. The tick species were identified by examining their morphological characteristics and by sequencing their COI gene and ITS-2 gene fragments. R. microplus was found in each studied region. In the ticks, we found DNA of Babesia bigemina, Anaplasma marginale, Anaplasma platys, and Ehrlichia spp. The results of this study indicate that R. microplus was introduced into Guinea with cows from Mali and/or Ivory Coast.

zoology↗

bioRxiv2018

The first reliable autochthonous case of ticks-borne encephalitis infection and detection of tick-borne encephalitis virus in Ixodes ricinus ticks and their hosts in an urban park of Moscow, Russia

Here, we report the first confirmed autochthonous tick-borne encephalitis case diagnosed in Moscow in 2016 and describe the detection of Tick-borne encephalitis virus (TBEV) in ticks and small mammals in a Moscow park.\n\nThe paper includes data from two patients who were bitten by TBEV-infected ticks within the Moscow city limits; one of these cases led to the development of the meningeal form of TBE. Both TBEV-infected ticks attacked patients in the same area. We collected ticks and trapped small mammals in this area in 2017. All samples were screened for the presence of pathogens causing tick-borne diseases by PCR. The TBEV-positive ticks and small mammals tissue samples were subjected to virus isolation. The sequencing of the complete polyprotein gene of the positive samples was performed.\n\nA total of 227 questing ticks were collected. TBEV was detected in five specimens of Ixodes ricinus. We trapped 44 small mammals, mainly bank voles (Myodes glareolus) and pygmy field mice (Apodemus uralensis). Two samples of brain tissue from bank voles yielded a positive signal in RT-PCR for TBEV. We obtained six virus isolates from the ticks and brain tissue of a bank vole. Complete genome sequencing showed that the obtained isolates belong to the European subtype and have low diversity with sequence identities as high as 99.9%. GPS tracking showed that the maximum distance between the exact locations where the TBEV-positive ticks were collected was 185 m. We assume that the forest park was free of TBEV and that the virus was recently introduced.

epidemiology↗