The Nigeria Centre for Disease Control and Prevention (NCDC) has reported that the country is still battling a significant diphtheria outbreak, with 41,336 suspected cases recorded across 37 states. These cases, spanning 350 local government areas, were reported between Epidemiological Week 19 of 2022 and Epidemiological Week 4 of 2025.
According to recent NCDC data, 24,846 cases (60.1%) were confirmed, 7,769 (18.8%) were discarded, 3,546 (8.6%) are still 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 one to 14 years, highlighting the severe impact on younger populations. However, only 20% (4,963) of confirmed cases were fully vaccinated with a diphtheria toxoid-containing vaccine, exposing significant gaps in vaccination coverage. The outbreak has resulted in 1,262 deaths among confirmed cases, reflecting 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). Together, these states account for 99.4% of all confirmed cases. In the most recent reporting period, eight suspected cases were identified in two states across 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 role of vaccination in tackling the outbreak, particularly as children account for the majority of cases. The agency has ramped up public health campaigns, improved surveillance, and deployed rapid response initiatives, especially in the hardest-hit states. It stressed that closing the vaccination gap is essential to prevent further spread and reduce the high fatality rate associated with the disease.
Diphtheria, a bacterial infection caused by Corynebacterium diphtheriae, primarily affects the mucous membranes of the throat and nose. The bacteria produce a toxin that can create a thick grey or white coating in the throat, making breathing difficult. In severe cases, it can damage the heart, nervous system, and other organs. Immunisation through the diphtheria vaccine remains the most effective preventive measure and is typically administered as part of routine childhood vaccinations.