The Nigeria Centre for Disease Control and Prevention (NCDC) has reported that the country is still grappling with a significant diphtheria outbreak, with a total of 41,336 suspected cases across 37 states. These cases, spanning 350 local government areas, have been reported between Epidemiological Week 19 of 2022 and Week 4 of 2025.
According to the latest NCDC data, 24,846 cases (60.1%) have been confirmed, 7,769 (18.8%) have been discarded, 3,546 (8.6%) are pending classification, and the status of 5,175 cases (12.5%) remains unknown. The outbreak is concentrated in a few states, with Kano leading with 23,784 suspected cases, followed by Yobe (5,302), Katsina (3,708), Bauchi (3,066), Borno (2,902), Kaduna (777), and Jigawa (364). These seven states account for 96.5% of all suspected cases.
Of the confirmed cases, 63.9% (15,845) occurred among children aged 1 to 14 years, indicating the severe impact on younger populations. However, only 20% (4,963) of these confirmed cases were fully vaccinated with the diphtheria toxoid-containing vaccine, revealing significant gaps in vaccination coverage. The outbreak has resulted in 1,262 deaths among confirmed cases, giving a Case Fatality Rate (CFR) of 5.1%.
The highest number of confirmed cases was reported in Kano (17,770), followed by Bauchi (2,334), Yobe (2,380), Katsina (1,088), Borno (1,036), Jigawa (53), Plateau (31), and Kaduna (44). These states collectively account for 99.4% of all confirmed cases. In the most recent reporting period, eight suspected cases were identified across two states and five local government areas. Six of these cases (75%) were confirmed as clinically compatible with diphtheria, with no deaths recorded, maintaining a zero CFR for the latest cases.
The NCDC emphasized the critical importance of vaccination in addressing the outbreak, particularly as children represent the majority of the cases. The agency has intensified public health campaigns, enhanced surveillance, and deployed rapid response measures, particularly in the most affected states. It has stressed the urgency of closing the vaccination gap to prevent further spread and reduce the high fatality rate associated with the disease.
Diphtheria, caused by the bacterium Corynebacterium diphtheriae, primarily affects the throat and nose mucous membranes. The bacteria produce a toxin that can form a thick grey or white coating in the throat, making breathing difficult. In severe cases, it can cause damage to the heart, nervous system, and other organs. Immunization through the diphtheria vaccine remains the most effective method of prevention and is typically included in routine childhood vaccination schedules.
