# The low genetic diversity of the Jingmen tick virus in Guinea sheds light on the recent introduction of the virus to West Africa

## TL;DR

This study finds that Jingmen tick virus in Guinea has low genetic diversity, suggesting a recent introduction through livestock trade, with certain tick species aiding its spread.

## Contribution

The study provides new insights into the recent introduction and spread of Jingmen tick virus in West Africa through genetic and epidemiological analysis.

## Key findings

- Jingmen tick virus in Guinea shows low genetic diversity, indicating a recent introduction.
- Three tick species are involved in virus circulation, with Rhipicephalus microplus likely facilitating spread.
- A reassortment event involving segment 3 was detected, highlighting the virus's adaptive potential.

## Abstract

Jingmen tick virus (JMTV), a segmented orthoflavi-like virus, has been recognized in recent years as a potential human and animal pathogen, with confirmed detections across Asia, Europe, Africa and South America. Recent JMTV surveillance data from Guinea has enabled detailed population genetic analysis to better understand the epidemiology of the virus in West Africa. Here, we report the results of a JMTV genetic diversity study and address specific issues of virus circulation in ticks parasitizing domestic animals.

A total of 928 ticks were collected from 114 host animals across 14 Guinean prefectures, and virus isolation was subsequently attempted in the tick Hyalomma anatolicum (HAE/CTVM8 cell line) cell culture. All collected ticks were morphologically identified, and PCR screening for JMTV was performed. Positive samples were subjected to either complete genome sequencing or targeted fragment sequencing.

Our sample included nine tick species, among which only three were involved in JMTV circulation: Rhipicephalus microplus, Rhipicephalus geigyi and Amblyomma variegatum. A total of 90 tick samples tested positive for JMTV. One JMTV strain was successfully isolated in the HAE/CTVM8 cell culture. Complete genomes (all 4 segments) were sequenced for six isolates to subsequently perform genetic diversity analysis, while a fragment of segment 3 was sequenced for 64 samples to assess genetic diversity and conduct haplotype analysis. We identified and mapped three natural foci and demonstrated potential JMTV circulation in some of these over 3 years. An analysis of the ticks collected from JMTV-exposed hosts showed 40.4% PCR positivity among attached ticks. Phylogenetic and haplotype analyses demonstrated a remarkably low genetic diversity among Guinean isolates, forming a monophyletic cluster with a star-like haplotype network topology; these are patterns consistent with recent viral introduction. We also detected a reassortment event involving segment 3.

These findings suggest that JMTV has recently been introduced to Guinea through livestock trade networks, with R. microplus ticks likely facilitating its spread. The evidence of reassortment highlights the adaptive potential of this virus in new ecosystems.

The online version contains supplementary material available at 10.1186/s13071-025-07089-z.