First detection and molecular characterization of Jingmen Tick Virus with a high occurrence in Rhipicephalus (Boophilus) microplus collected from livestock in Cameroon (2024)

Background. Jingmen tick virus (JMTV) is a novel tick-borne virus detected for the first time in Riphicephalus (Boophilus) microplus in China. To date, there is no information regarding the circulation of JMTV in ticks collected from livestock in Cameroon. This study aims to assess the presence of JMTV in ticks collected from livestock (cattle and sheep) in an area of the Akonolinga health district, Center region, Cameroon. Methods. A cross sectional study was carried out during the dry season between the 5th to 14th march 2024. Ticks were collected from cattle and sheep in six sampling sites in an area approximately 30 km long and 18 km wide along the Nyong river, in central Cameroon. Ticks were identified morphologically and molecularly. Total RNA/DNA was extracted from tick pools and screened for JMTV RNA using a segment 2 RT-qPCR system. Positive JMTV pools were sequenced for partial JMTV-Segment 1 and full genome analyses. Results. A total of 622 ticks, organized in 251 pools were collected from 155 cattle and 9 sheep. They consisted of five species covering three genera: R. (B.) microplus (472; 75.88%), Amblyomma variegatum (118; 18.97%), Hyalomma truncatum (13; 2.09%), Hyalomma rufipes (2; 0.32%), and other Rhipicephalus spp. (17; 2.73%). The qRT-PCR screening of 251 tick pools yielded 61 JMTV-positive pools of which 58 corresponded to R. (B.) microplus . Multiple sequence analysis revealed that JMTV from the Akonolinga area shared > 95% identity with strains from Guinea, and that these strains clustered phylogenetically together. Conclusions. We provided molecular evidence of the presence of JMTV in R. (B.) microplus and A. variegatum collected from cattle and sheep from an area not yet recognized as endemic for this virus confirming the wide geographical distribution of JMTV.