2.1. Study setting
This study was carried out in the NW Region of Cameroon. This region is a home to close to 2.5 million inhabitants, majority of whom reside in rural areas where they are involved in farming for their livelihood. Over 40% of the population is aged 18 years and above.
The region has a total of 19 health districts and each of these districts is led by a district medical officer. Each health district is further sub-divided into health areas (247 health areas in total for the region), which are led by a chief of health area, who by default is the head of the leading health facility within the health area. Each of these health areas has at least one health facility which could be public or private .
The region lacked a robust laboratory diagnostic capacity which could identify and characterize emergent pathogens including SARS COV-2. For instance, during the onset of the pandemic, samples collected from the region had to be shipped to Centre Pasteur of Cameroon located in the center region for analysis. This invariably affected the turnaround time for returning the results to patients. From June, 2020, like in the rest of the country, the region benefitted from rapid antigen screening test which permitted quick identification of cases in all major health facilities across the region . In addition, COVID-19 care centers were set up in the region for the management cases .
In April, 2021, Covid-19 vaccination centers were set up to support the delivery of Covid-19 vaccines to persons 18 years and above. In total, 23 vaccination centers were identified and accredited across the region, with each health district having at least one vaccination site. These sites began delivering Sinopharm and Covishield vaccines in April, 2021 and given in two doses separated by 3 weeks and 8 weeks respectively for full immunization. Johnson and Johnson vaccine was later added in July 2021 given as a single dose for complete immunization. Vaccination services against covid are offered in these fixe vaccination sites on daily basis and in the community during outreach vaccination activities.
2.2. Study procedure
The data for this cross-sectional study were collected from August to September 2021. Covid-19 surveillance data were obtained from weekly epidemiological reports from the region and the national public health operation center. The covid-19 vaccination data were obtained from the district health information software (Dhis)-2. A pretested questionnaire was used to abstract key variables, including the security profile of the health districts of the region from 2020 to September, 2021. This security situation was updated to the already existing data for the previous four years as reported earlier . The questionnaires were filled by the regional and district managers of the NW region. The investigation team then resolved any identified data discrepancy by directly calling the regional head or the district medical officers concerned.
2.3. Data management and analysis.
The data were analyzed with Microsoft Office Excel 2019 and summary statistics was used to estimate incidence, prevalence, case fatality and vaccination coverage. In addition, Quantum Geographic Information System (QGIS) was used to spatially display the security status of the region in maps.