DAKAR, Senegal: At least 20 people have died in Senegal following an outbreak of Rift Valley fever that began in late September, the country’s Ministry of Health said on Wednesday.
The viral disease, which primarily affects animals but can also infect humans, has severely impacted the northern Saint Louis region, where 159 of the 171 confirmed cases have been reported, according to a ministry statement released.
The first laboratory-confirmed case in Senegal was recorded on September 20.
Since the start of the outbreak, authorities have reported 20 fatalities and 128 recoveries. However, no official data has been released regarding livestock deaths linked to the disease.
In humans, Rift Valley fever commonly causes flu-like symptoms such as fever, muscle and joint pain, and headaches. In animals, it often leads to fever and internal bleeding.
The Institut Pasteur de Dakar has since published a molecular analysis of the virus, confirming that this outbreak belongs to lineage H — a strain previously seen in Senegal’s 2020 and 2022 clusters and in Mauritania’s 2020 outbreak.
The study, released on Virological.org, underscores that the virus has likely persisted locally rather than being newly introduced, pointing to ongoing environmental and ecological drivers.
Experts attribute the outbreak to unusual weather patterns—marked by alternating periods of heavy rainfall and heat—that have expanded mosquito breeding habitats and accelerated the spread of the virus. These conditions reflect a broader trend of climate-driven disease emergence, where changing environments allow vector populations to thrive in previously unaffected areas.
