Authorities in Oyo State (a southwestern Nigerian state whose capital is Ibadan) have confirmed a fatal case of Lassa fever following the death of a 44-year-old woman who was being treated at the University College Hospital, Ibadan; laboratory confirmation was received on 13 April. The state government has activated its Incident Management System to coordinate the response, including contact tracing, monitoring of those exposed, and heightened surveillance across all health facilities. Lassa fever is a rodent-borne viral haemorrhagic illness that is preventable and treatable if caught early, and officials are urging residents to seek prompt medical care if they develop symptoms such as persistent fever, unexplained bleeding, or breathing difficulties.