The Nigeria Centre for Disease Control and Prevention has confirmed 143 cases of Lassa fever out of the 484 suspected cases from December 30, 2024, to January 12, 2025, in seven states across 32 local government areas.
The centre also reported 22 deaths with a case fatality rate of 15.4 per cent.
This is according to the Lassa fever situation report obtained from the NCDC on Wednesday.
The report showed that the deaths were recorded in Ondo (six); Edo (five); Bauchi (two); Taraba (six); Ebonyi (two); and Gombe (one).
According to the World Health Organisation, Lassa fever is an acute viral haemorrhagic illness caused by the Lassa virus, a member of the arenavirus family of viruses.
Humans usually become infected with the Lassa virus through exposure to food or household items, contaminated with urine or faeces of infected Mastomys rats.
The disease is endemic in the rodent population in parts of West Africa.
Lassa fever is known to be endemic in Benin, Ghana, Guinea, Liberia, Mali, Sierra Leone, Togo, and Nigeria.
“Person-to-person infections and laboratory transmission can also occur, particularly in healthcare settings in the absence of adequate infection prevention and control measures,” the global health body stated.
The report read partly, “In week two, the number of new confirmed cases increased from 54 in epi week one, of 2025 to 89. These were reported in Ondo, Edo, Taraba, Bauchi, Gombe, Kogi, and Ebonyi States.
“Cumulatively in week two, 2025, 22 deaths have been reported with a CFR of 15.4 per cent, which is lower than the CFR for the same period in 2024 (16.4 per cent).
“In total for 2025, seven states have recorded at least one confirmed case across 32 Local Government Areas.”
The report stated that 77 per cent of all confirmed Lassa fever cases were reported from these three states (Ondo, Edo, and Bauchi) while 23 per cent were reported from four states with confirmed Lassa fever cases.
“Of the 77 per cent confirmed cases, Ondo reported 38 per cent, Edo 22 per cent, and Bauchi 17 per cent.
“The predominant age group affected is 21-30 years (Range: Three to 78 years, Median Age: 32 years). The male-to-female ratio for confirmed cases is 1:0.7,” it added.
It stated that the number of suspected cases decreased compared to that reported for the same period in 2024.
It added that one new healthcare worker was affected in the reporting week.
It noted that the National Lassa fever multi-partner, multi-sectoral Incident Management System had been activated to coordinate the response activities at all levels.
