Between January and November 2023, Nigeria experienced a significant measles outbreak. Data from the Nigeria Centre for Disease Control and Prevention (NCDC) indicate 19,213 confirmed cases and 153 deaths within this 11-month period. These figures are based on 26,866 suspected cases reported across 507 Local Government Areas (LGAs) in all 36 states and the Federal Capital Territory.

Measles is an acute viral illness characterized by high transmissibility and potential for severe complications, especially in children. The virus spreads via respiratory droplets and contaminated surfaces, remaining viable for up to two hours. Individuals are most infectious from four days before to four days after rash onset.

The distribution of cases has been uneven. In the most recent month analyzed, five states,Delta, Kwara, Bayelsa, Jigawa, and Akwa Ibom,accounted for over 50% of the 71 suspected cases reported nationwide. Only one case was laboratory-confirmed during this period, with no associated deaths.

From January to November, Borno, Zamfara, Yobe, Bauchi, and Kebbi states accounted for more than 66% of all suspected cases. Of the 19,213 confirmed cases, 2,791 were laboratory-confirmed, 2,013 were epidemiologically linked, and 14,409 were classified as clinically compatible. Additionally, 6,440 suspected cases were discarded, and 1,213 cases remained pending classification at the time of reporting.

Children aged 9 to 59 months represented nearly 50% of all confirmed cases, indicating a high vulnerability in this demographic. The case fatality rate among confirmed cases was 0.8%, with 153 deaths recorded.

Vaccination coverage among affected individuals was low. Of the 19,213 confirmed cases, 14,801 (77%) had not received any dose of the measles vaccine. This high proportion of unvaccinated cases highlights gaps in routine immunization and access, particularly in hard-to-reach and conflict-affected areas.

Geographically, the outbreak affected 188 LGAs across 27 states. By the end of the reporting period, only one LGA (Eti-Osa in Lagos State) had an ongoing outbreak; all others had been declared over. The NCDC continues surveillance and coordination with state and local health authorities.

In response, the Nigerian government launched an integrated Measles-Rubella vaccination campaign, targeting approximately 106 million children aged nine months to under 15 years. This campaign, the largest of its kind in Africa, also includes polio and HPV vaccination components.

Health experts have identified the campaign as a necessary intervention to address immunity gaps. However, they emphasize the need for sustained investment in routine immunization, community engagement, and health system strengthening to achieve long-term control of measles and other vaccine-preventable diseases.

The 2023 measles outbreak in Nigeria demonstrates the direct relationship between low vaccination coverage and increased disease incidence. Data support the conclusion that improving immunization rates is essential for reducing morbidity and mortality associated with measles.