Burden of measles in Nigeria: a five-year review of casebased surveillance data, 2012-2016.

Introduction: measles is a vaccine preventable, highly transmissible viral infection that affects mostly children under five years. We reviewed surveillance data on measles from Nigeria over a five-year period to highlights its burden and make recommendations for improvements.

Methods: we conducted a secondary data analysis of measles specific Integrated Disease Surveillance and Response (IDSR) records of all states in Nigeria over a five-year period.

Results: a total of 131,732 cases were recorded between January 2012 and September 2016. Most cases 57,892 (43.95%) were recorded in 2013 while the least 11,061 (8.4%) were recorded in 2012. A total of 817 deaths were recorded, with a case fatality rate (CFR) of 0.62%. The highest CFR (1.43%) was recorded in 2012 while the least CFR (0.44%) was recorded in 2016. Only 8,916 (6.7%) cases were confirmed by laboratory tests. The trend of measles cases followed the same pattern throughout the years under review, with cases peaking at March, then gradually reducing to lowest level at June, which was maintained throughout the rest of the year. States in northern region of Nigeria recorded the highest attack rate (Yobe: 480.29 cases per 100,000 population, Sokoto: 284.63 cases per 100,000 population and Katsina: 246.07 cases per 100,000 population) compared to States in the southern region (Rivers: 11.72 cases per 100,000 population and Akwa Ibom: 13.59 cases per 100,000 population). Conversely, States in the southern region recorded the highest CFR (Ebonyi: 13.43% and Rivers: 3.27%).

Conclusion: measles infection remains a burden especially in the northern region of Nigeria. Although measles fatalities declined over the years, laboratory confirmation was sub-optimal. We recommended improvement on routine immunization and strengthening of regional laboratories diagnostic capacities, for successful eradication of measles from Nigeria.