Prevalence and associated factors of human haemorrhagic fevers in Senegal: a comprehensive analysis of Hantaan, Crimean-Congo haemorrhagic fever and Rift Valley fever

This study provides serological evidence of human hantavirus exposure in Senegal and confirms subclinical circulation of Rift Valley and Crimean-Congo haemorrhagic fevers. Our results suggest that routine surveillance is missing the vast majority of infections. These viruses circulate endemically within exposed populations, often in an asymptomatic or subclinical state, or manifesting with mild symptoms. This under-detection by the current monitoring system poses a significant challenge to the implementation of effective control strategies in endemic regions. This highlights the need to strengthen One Health surveillance to ensure early warning and public health preparedness.