Some 8,057 suspected meningitis cases - most of them children - have been reported since the disease surfaced in December. More than 250 have died in just over a week, taking the total to 745.
Most cases are in the northern states of Zamfara, Katsina, Kebbi, Niger and Sokoto and there are fears that this outbreak could again spread across the border into Niger, the Nigeria Centre for Disease Control said on Wednesday.
Nigeria is one of 26 countries in Sub-Saharan Africa where large meningitis epidemics tend to occur. Outbreaks tend to peak in the dry season due to low humidity and dusty conditions and end when the rainy season arrives.
Fighting the disease
The Nigerian federal government said it has started a nationwide vaccination campaign aiming to cover millions of people.
The World Health Organization (WHO) said last week that a vaccination campaign run by the International Coordinating Group on Vaccine Provision is also underway in Nigeria.
If untreated, fatal in 50 percent of cases
Meningitis is an infection of the thin lining that surrounds the brain and spinal cord and can cause brain damage.
It is caused by various types of bacteria, six of which can cause epidemics, and is transmitted between people through coughs and sneezes and facilitated by cramped living conditions and close contact.
Untreated, meningococcal meningitis - the bacterial form of the disease - is fatal in 50 percent of cases. Even when the disease is diagnosed early and treatment begins, 5 percent to 10 percent of patients die, usually within 24 to 48 hours of the onset of symptoms.
A meningitis epidemic killed 1,100 people and infected more than 10,000 in Nigeria and neighboring Niger in 2015.
jbh/msh (AP, AFP)