Crimean-Congo Hemorrhagic Fever virus (CCHFV) is a zoonotic arbovirus of major public health concern, transmitted to humans and animals by ticks or infected animals. Although previous evidence of CCHFV circulation was reported in central and southeastern bioecological areas of Senegal, its spatial and temporal dynamics remain poorly understood. To investigate CCHFV activity, naïve sheep and goats were placed near human populations as sentinel herds in the areas from March 2021 to June 2024. Blood and tick samples were regularly collected from these animals. Sera were tested by ELISA for CCHFV antibodies, while ticks were screened by RT-PCR for CCHFV RNA. A total of 2,708 sera were tested, and an overall seroconversion of 16.83% (95% CI: 14.46-19.42%) was recorded. Variations in CCHFV infection rate (CCHFVIR) were not significant between central and southeastern zones, but highly significant between districts within each area. Goats were significantly more likely to be infected than sheep (OR = 1.47; 95% CI: 1.03-2.11; p = 0.035). The CCHFVIR was significantly higher during the dry season (dry: 21.77%; 95% CI: 17.80-26.17% vs rainy: 13.08%; 95% CI: 10.30-16.28%, p = 0.001). Seasonal fluctuations in tick vector abundance appeared to closely correlate with seroconversion dynamics in sentinel herds, even if they are no tick pools positive for CCHFV by RT-PCR. This study showed permanent circulation of CCHFV in both areas and suggests that rainfall patterns, host species, and geographic location are key factors in CCHFV transmission risk. A One Health approach associating animal, human, and environmental surveillance needs to be implemented to control CCHF emergence and spread.