Detection of Crimean-Congo Haemorrhagic Fever Virus from Livestock Ticks in Northern, Central and Southern Senegal in 2021

Crimean-Congo haemorrhagic fever virus (CCHFV) occurs sporadically in Senegal, with a few human cases each year. This active circulation of CCHFV motivated this study which investigated different localities of Senegal to determine the diversity of tick species, tick infestation rates in livestock and livestock infections with CCHFV. The samples were collected in July 2021 from cattle, sheep and goats in different locations in Senegal. Tick samples were identified and pooled by species and sex for CCHFV detection via RT-PCR. A total of 6135 ticks belonging to 11 species and 4 genera were collected. The genus Hyalomma was the most abundant (54%), followed by Amblyomma (36.54%), Rhipicephalus (8.67%) and Boophilus (0.75%). The prevalence of tick infestation was 92%, 55% and 13% in cattle, sheep and goats, respectively. Crimean-Congo haemorrhagic fever virus (CCHFV) was detected in 54/1956 of the tested pools. The infection rate was higher in ticks collected from sheep (0.42/1000 infected ticks) than those from cattle (0.13/1000), while all ticks collected from goats were negative. This study confirmed the active circulation of CCHFV in ticks in Senegal and highlights their role in the maintenance of CCHFV. It is imperative to take effective measures to control tick infestation in livestock to prevent future CCHFV infections in humans.

Automated summary

This study investigated the diversity of tick species, tick infestation rates in livestock, and livestock infections with Crimean-Congo haemorrhagic fever virus (CCHFV) in different localities of Senegal. The results showed a high prevalence of tick infestation and the presence of CCHFV in tick samples. It confirms the active circulation of CCHFV in ticks and highlights the need for effective measures to control tick infestation in livestock and prevent future infections in humans.