At least, 19 out of the states of the federation have been affected by Lassa fever.
The Nigeria Centre for Disease Control (NCDC) made this known on Thursday on its website.
It said the current outbreak of the disease started in December 2016 and each of the 19 states had recorded at least one case.
States affected are Ogun, Bauchi, Plateau, Ebonyi, Ondo, Edo, Taraba, Nasarawa, Rivers, Kaduna, Gombe, Cross River, Borno, Kano, Kogi, Enugu, Anambra, Kwara and Lagos.
Most affected of the states are: Ondo, Edo, Plateau, Bauchi, Ogun, Kaduna, Kwara and Lagos states.
In its statistics, NCDC said a total of 263 cases had been classified, 249 confirmed and 85 deaths recorded.