Evaluation of measles and rubella public health laboratory surveillance performance in Nigeria
Kayode Akanbi, Olaniyi Felix Sanni, Akyala Ishaku Adamu, Michael Idoko Abah, Sola Thomas Sunday, Islamiyyat Adekemi OlatinwoAbstract
Background:
Measles and rubella remain major vaccine-preventable diseases in Nigeria, with persistent transmission and heterogeneous surveillance performance across different regions. This study assessed the performance of Nigeria’s public health laboratory surveillance system for measles and rubella.
Materials and Methods:
A retrospective quantitative study was conducted using national measles and rubella surveillance data collected between 2014 and 2023 and laboratory performance data from 2016 to 2023. Data were obtained from the Nigeria Center for Disease Control and eight national measles/rubella reference laboratories. All eligible records were included in the analysis. Descriptive statistics and time-series analyses were performed to evaluate the surveillance trends before, during, and after the coronavirus disease 2019 (COVID-19) pandemic. Statistical analyses were conducted using IBM SPSS Statistics version 28.
Results:
Of all laboratory-confirmed measles cases, 79.3% occurred among children aged 1–4 years, while 78.0% of laboratory-confirmed rubella cases were reported in the same age group. Infants aged less than 1 year accounted for 19.9% of confirmed measles cases and 18.9% of confirmed rubella cases. Geographically, the highest numbers of laboratory-confirmed measles cases were reported in Katsina (2039), Kebbi (1632), and Jigawa (1349). In contrast, the greatest numbers of confirmed rubella cases were recorded in Abia (329), Delta (317), and Plateau (308). The measles-to-rubella case ratio declined from 9.02:1 in 2014 to 2.8:1 in 2023, indicating a reduction in measles incidence alongside improved rubella detection through strengthened integrated surveillance. The surveillance performance varied over time, with the highest laboratory confirmation rates observed in 2020 (32.1%) and 2023 (25.4%). The proportion of discarded specimens reached its highest level in 2023 (69.7%). The COVID-19 pandemic adversely affected surveillance activities, resulting in a marked decline in confirmed cases during the peak of the pandemic, followed by progressive recovery in 2022–2023.
Conclusion:
Measles and rubella continue to disproportionately affect young children in Nigeria and demonstrate considerable geographic variation, accompanied by inconsistent surveillance performance. Strengthening laboratory infrastructure, ensuring a continuous supply of diagnostic reagents, expanding workforce capacity, and implementing robust digital surveillance and reporting systems are essential to enhance surveillance effectiveness and support measles and rubella control and elimination efforts.