Descriptive Characterization of Epidemic Meningococcal Serogroup W in the Upper West Region of Ghana

Abstract

Aims: In recent time, Nm W outbreaks have been on the increase in the African meningitis ‘belt’. One of such outbreaks occurred in the Upper West Region of Ghana from December, 2015 to April 2016. The epidemiological features of the outbreak are descriptively characterized and an overview of the reactive vaccination provided. Study Design: Descriptive. Place and Duration of Study: Upper West Region of Ghana from December, 2015 to April 2016. Methods: Data on all cases of meningitis during the outbreak was obtained from the Disease Surveillance Department of the Ghana Health Service. Variables such as age, sex, district of residence, reporting district, health facility reported, date seen at health facility, date of onset, laboratory results, outcome and vaccination coverage were used for all analysis. Results: Between epidemiologic weeks 1 and 7 of the outbreak, the predominant causative organism was Neisseria meningitidis (Serogroup Nm W) forming 70% of all bacterial meningitis cases recorded. Nadowli-Kaleo, Jirapa and Nandom recorded the highest number of confirmed cases with the cases crossing epidemic thresholds in weeks 5,4 and 5 respectively. Majority of confirmed Nm W cases (46 cases) were found in ages 15 years and above. A reactive vaccination campaign was undertaken following the outbreak and a target coverage of 98.4% achieved. Conclusion: Neisseria meningitidis serogroup NmW is increasingly becoming a major cause of bacterial meningitis and there is the need to institute effective control measures to mitigate its effects. Urbanized areas like Jirapa, Nadowli-Kaleo, Lawra and Nandom districts should have alert and epidemic thresholds reviewed frequently to facilitate early detection and improve early and effective response including vaccination.