Abuja, April 16 : The death toll of the Lassa fever outbreak in Nigeria has risen to 127, public health authorities said.

A total of 674 confirmed cases have been recorded from 4,025 suspected cases reported since the onset of the outbreak in January, the Nigeria Centre for Disease Control and Prevention (NCDC) said in a statement on Tuesday.

Eighteen out of the 36 states in the most populous African country have been affected by the viral hemorrhagic disease so far this year, with the southern states of Ondo and Edo and the northern state of Bauchi the worst-hit, accounting for more than 70 per cent of the total confirmed cases, the NCDC said.

The NCDC put the case fatality rate at 18.8 per cent, slightly higher than the 18.5 per cent reported during the same period in 2024.

Young adults between the ages of 21 and 30 are the most affected, with the median age of infection reported at 30 years, the public health agency said. It noted that more males than females had been affected, with a male-to-female ratio of 1:0.8.

The NCDC identified poor health-seeking behaviour, high treatment costs in some areas, and limited awareness in high-burden communities as major challenges. It has activated a multi-sectoral incident management system to coordinate nationwide response efforts, Xinhua news agency reported.

In 2024, Nigeria reported 214 deaths from Lassa fever, according to the NCDC.

According to the World Health Organisation, Lassa fever is an acute viral haemorrhagic illness caused by Lassa virus, a member of the arenavirus family of viruses.

Humans usually become infected with 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.

Person-to-person infections and laboratory transmission can also occur, particularly in healthcare settings in the absence of adequate infection prevention and control measures.

Diagnosis and prompt treatment are essential. The overall case-fatality rate is 1 per cent. Among patients who are hospitalised with severe clinical presentation of Lassa fever, case-fatality is estimated at around 15 per cent. Early supportive care with rehydration and symptomatic treatment improves survival.

About 80 per cent of people who become infected with Lassa virus have no symptoms and 1 in 5 infections result in severe disease, where the virus affects several organs such as the liver, spleen and kidneys.

/IANS