Effects of Mass Vaccination against Meningococus On Childhood Morbidity and Mortality in Yobe State, Northeast Nigeria

Meningitis is a deadly disease that poses profound public health threats and responsible for outbreaks and death of children mainly in the meningitis belt of Africa. This study was designed to determine the effectiveness of mass vaccination against Meningitis in Yobe State, Northeast Nigeria. An ecological study design involving the collection of secondary data from Yobe State Epidemiological unit based on the Integrated Disease Surveillance Response System template was done. The outcomes measured include the morbidity and mortality from meningitis across all the local government areas in Yobe State. This involved the collection of all the meningitis cases that were reported within the period under review (2017-2018). A comparative analysis of the morbidity and mortality from meningitis before (pre) and after (post) mass vaccination against the disease was made. The mass vaccination intervention was conducted within the first week of February 2018 and the effects of this intervention was measured. A paired sample t-test was done using the Statistical Package for Social Sciences (SPSS) windows version 22 to determine the relationship between mass vaccination and morbidity and mortality from meningitis. Result revealed that a total of 480 cases were reported during the study period, 415(86.5%) in 2017 (pre mass vaccination and 65(13.5%) were reported in 2018 (post vaccination). 53 deaths out of the 480 total number of cases were recorded and the Case Fatality Rate (CFR) = 11.04% was estimated during the study. Majority 43(81.13) of the deaths occurred in 2017 while the remaining 10(18.87) were reported in 2018 when mass vaccination against meningitis was conducted. Mass vaccination resulted in a 72.9% decline in the number of cases and a 62.3% decline in the number of deaths from meningitis in Yobe State during the study period. There was a statistically significant difference in the number of cases of meningitis before (pre) and after (post) the mass vaccination. Mean 12.5, (95% CI: -5.892 to 30.892) with alpha set at 0.05, P = 0.045. However, there was no statistically significant difference in the number of deaths associated with meningitis, Mean 2.750, (95% CI: -2.097 to 7.597) with alpha set at 0.05, P = 0.646. Mass vaccination against meningitis therefore confers herd immunity to populations with a subsequent significant decline in morbidity associated with the infection. It is therefore important for mass vaccination against meningitis to be intensified in order to control, possibly eliminate and eradicate the disease in Sub-Saharan Africa with a high burden of the infection in the meningitis belt.