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 Rhipicephalus (Boophilus) microplus in China. To date, there is no information regarding the circulation of JMTV in ticks collected from livestock in Cameroon. As part of the surveillance for arboviral circulation, this study aimed 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 5 and 14 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 into 251 pools were collected from 155 cattle and nine sheep. They consisted of five species covering three genera: R. (B.) microplus (472; 75.9%), Amblyomma variegatum (118; 19.0%), Hyalomma truncatum (13; 2.1%), Hyalomma rufipes (2; 0.3%), and other Rhipicephalus spp. (17; 2.7%). The quantitative reverse transcription polymerase chain reaction (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 provide 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 its wide geographical distribution.
Competing Interests: Declarations. Ethics approval and consent to participate: The study protocol was implemented with approval from the Regional Delegation of the Ministry of Livestock, Fisheries, and Animal Industries (MINEPIA), authorization No. 1325/L/MINEPIA/SG/DREPIA-CE/SRDPIA. Oral consent for ticks sampling was obtained from the animals’ owners. Pastoralist herdsmen were visited either at their homesteads or at a convenient location in the vicinity where the cattle could be examined. The translator/research assistant explained the project in either Fulfulde, Pidgin, English, or French, and the herdsman or farmer was asked to give verbal consent to participate in the study. Consent for publication: Not applicable. Competing interests: The authors declare no competing interests.
(© 2025. The Author(s).)