Impact of Supplementary Immunization Activities using Novel Oral Polio Vaccine Type 2 during a Large outbreak of Circulating Vaccine-Derived Poliovirus in Nigeria.

BACKGROUND: Novel oral poliovirus vaccine (OPV) type 2 (nOPV2) has been made available for outbreak response under an emergency use listing authorization based on supportive clinical trial data. Since 2021 more than 350 million doses of nOPV2 were used for control of a large outbreak of circulating vaccine-derived poliovirus type 2 (cVDPV2) in Nigeria. METHODS: Using a bayesian time-series susceptible-infectious-recovered model, we evaluate the field effectiveness of nOPV2 immunization campaigns in Nigeria compared with campaigns using monovalent OPV type 2 (mOPV2). RESULTS: We found that both nOPV2 and mOPV2 campaigns were highly effective in reducing transmission of cVDPV2, on average reducing the susceptible population by 42% (95% confidence interval, 28-54%) and 38% (20-51%) per campaign, respectively, which were indistinguishable from each other in this analysis (relative effect, 1.1 [.7-1.9]). Impact was found to vary across areas and between immunization campaigns. CONCLUSIONS: These results are consistent with the comparable individual immunogenicity of nOPV2 and mOPV2 found in clinical trials but also suggest that outbreak response campaigns may have small impacts in some areas requiring more campaigns than are suggested in current outbreak response procedures.

The role of supportive supervision using mobile technology in monitoring and guiding program performance: a case study in Nigeria, 2015-2016.

BACKGROUND: Supportive supervision is one of the interventions that fosters program improvement by way of imparting knowledge and skills to health workers. The basic challenge in supportive supervision is the availability of data in real time for timely and effective feedback. Thus, the main objective of this study was to determine the contribution of real-time data collection during supportive supervision for timely feedback and generation of evidence for health intervention planning. METHODS: We analyzed supportive supervision records collected through handheld devices employing the open data kit (ODK) platform from July 2015 to June 2016. Supervision was conducted across the country by 592 World Health Organization (WHO) officers. The availability of real-time data and the distance of health facilities to the community were analyzed. RESULTS: During the study period, 90,396 health facilities were supervised. The average time spent during supervision varied from 1.53 to 3.78 h across the six geopolitical zones of the country. The average interval between completion of the supervisory checklist and synchronization with the server varied from 3.9 h to 7.5 h. The average distance between the health facility and a ward varied from 5 to 24 km. CONCLUSION: The use of handheld devices for supportive supervision provided real-time data from health facilities to state and zonal levels for analysis and feedback. Program officers used the findings to rectify process indicators in time for a better outcome.

Lessons learnt from implementing community engagement interventions in mobile hard-to-reach (HTR) projects in Nigeria, 2014-2015.

BACKGROUND: The year 2014 was a turning point for polio eradication in Nigeria. Confronted with the challenges of increased numbers of polio cases detected in rural, hard-to-reach (HTR), and security-compromised areas of northern Nigeria, the Nigeria polio program introduced the HTR project in four northern states to provide immunization and maternal and child health services in these communities. The project was set up to improve population immunity, increase oral polio vaccine (OPV) and other immunization uptake, and to support Nigeria's efforts to interrupt polio transmission by 2015. Furthermore, the project also aimed to create demand for these services which were often unavailable in the HTR areas. To this end, the program developed a community engagement (CE) strategy to create awareness about the services being provided by the project. The term HTR is operationally defined as geographically difficult terrain, with any of the following criteria: having inter-ward/inter-Local Government Area/interstate borders, scattered households, nomadic population, or waterlogged/riverine area, with no easy to access to healthcare facilities and insecurity. METHODS: We evaluated the outcome of CE activities in Kano, Bauchi, Borno, and Yobe states to examine the methods and processes that helped to increase OPV and third pentavalent (penta3) immunization coverage in areas of implementation. We also assessed the number of community engagers who mobilized caregivers to vaccination posts and the service satisfaction for the performance of the community engagers. RESULTS: Penta3 coverage was at 22% in the first quarter of project implementation and increased to 62% by the fourth quarter of project implementation. OPV coverage also increased from 54% in the first quarter to 76% in the last quarter of the 1-year project implementation. CONCLUSIONS: The systematic implementation of a CE strategy that focused on planning and working with community structures and community engagers in immunization activities assisted in increasing OPV and penta3 immunization coverage.

Profile of polio-compatible cases in Nigeria, 2006-2016.

BACKGROUND: The tremendous progress made by Nigeria towards polio eradication has recently suffered a setback with the isolation of circulating vaccine-derived poliovirus (cVDPV) type 2 from environmental samples and confirmation of four wild poliovirus (WPV) cases from acute flaccid paralysis (AFP) cases, with dates of onset of paralysis in July and August 2016. All these viruses were confirmed from the security-challenged northeastern state of Borno. Polio-compatible cases exist in Nigeria, and they indicate surveillance failure. Surveillance, therefore, has to be strengthened for the country to achieve certification. The objective of this paper is to highlight the epidemiological profile and magnitude of polio-compatible cases in Nigeria during the reporting period, as well as immunization and surveillance response activities conducted to close immunity and surveillance gaps. METHODS: We conducted a retrospective review of AFP surveillance performance and polio-compatible cases in Nigeria between 2006 and 2016 from the AFP database at the World Health Organization Country Office. We also reviewed and compared key epidemiological features of polio-compatible cases with those of wild poliovirus cases during the reporting period. RESULTS: The non-polio AFP rate improved from 6.5 in 2006 to 19.5 in 2016. The corresponding figures for stool adequacy rates were 88 and 98%. The total number of polio-compatible cases reported during the reporting period was 888, with the highest number (194) of cases reported in 2006 and the least (24) in 2016. Clusters of polio-compatible cases were reported every year during the reporting period except in 2015. The highest number (65) of polio-compatible cases in clusters was reported in 2006. The key epidemiological features of polio-compatible and wild poliovirus cases were similar. CONCLUSION: AFP surveillance performance has improved significantly during the reporting period. Surveillance gaps still existed as shown by the presence of orphan viruses and polio-compatible cases, and these gaps need to be identified and closed to achieve certification.

Tracking Vaccination Teams During Polio Campaigns in Northern Nigeria by Use of Geographic Information System Technology: 2013-2015.

INTRODUCTION: Nigeria is among the 3 countries in which polio remains endemic. The country made significant efforts to reduce polio transmission but remains challenged by poor-quality campaigns and poor team performance in some areas. This article demonstrates the application of geographic information system technology to track vaccination teams to monitor settlement coverage, reduce the number of missed settlements, and improve team performance. METHODS: In each local government area where tracking was conducted, global positioning system-enabled Android phones were given to each team on a daily basis and were used to record team tracks. These tracks were uploaded to a dashboard to show the level of coverage and identify areas missed by the teams. RESULTS: From 2012 to June 2015, tracking covered 119 immunization days. A total of 1149 tracking activities were conducted. Of these, 681 (59%) were implemented in Kano state. There was an improvement in the geographic coverage of settlements and an overall reduction in the number of missed settlements. CONCLUSIONS: The tracking of vaccination teams provided significant feedback during polio campaigns and enabled supervisors to evaluate performance of vaccination teams. The reports supported other polio program activities, such as review of microplans and the deployment of other interventions, for increasing population immunity in northern Nigeria.

Implementation of a Systematic Accountability Framework in 2014 to Improve the Performance of the Nigerian Polio Program.

BACKGROUND: An accountability framework is a central feature of managing human and financial resources. One of its primary goals is to improve program performance through close monitoring of selected priority activities. The principal objective of this study was to determine the contribution of a systematic accountability framework to improving the performance of the World Health Organization (WHO)-Nigeria polio program staff, as well as the program itself. METHODS: The effect of implementation of the accountability framework was evaluated using data on administrative actions and select process indicators associated with acute flaccid paralysis (AFP) surveillance, routine immunization, and polio supplemental immunization activities. Data were collected in 2014 during supportive supervision, using Magpi software (a company that provides service to collect data using mobile phones). A total of 2500 staff were studied. RESULTS: Data on administrative actions and process indicators from quarters 2-4 in 2014 were compared. With respect to administrative actions, 1631 personnel (74%) received positive feedback (written or verbal commendation) in quarter 4 through the accountability framework, compared with 1569 (73%) and 1152 (61%) during quarters 3 and 2, respectively. These findings accorded with data on process indicators associated with AFP surveillance and routine immunization, showing statistically significant improvements in staff performance at the end of quarter 4, compared with other quarters. CONCLUSIONS: Improvements in staff performance and process indicators were observed for the WHO-Nigeria polio program after implementation of a systematic accountability framework.

Strengthening Routine Immunization in Areas of Northern Nigeria at High Risk for Polio Transmission During 2012-2014.

BACKGROUND: Following the 2012 declaration by World Health Organization (WHO) Regional Director for Africa and the WHO Executive Board to ramp up routine immunization (RI) activities, began to intensify activities to strengthen RI. This study assessed how the intensification of RI helped strengthen service delivery in local government areas (LGAs) of northern Nigeria at high risk for polio transmission. METHODS: A retrospective study was performed by analyzing RI administrative data and findings from supportive supervisory visits in 107 high-risk LGAs. RESULTS: Our study revealed that administrative coverage with 3rd dose of diphtheria-pertussis-tetanus vaccine in the 107 high-risk LGAs improved from a maximum average coverage of 33% during the preintensification period of 2009-2011 to 74% during the postintensification period of 2012-2014. CONCLUSIONS: Routine immunization could be strengthened in areas where coverage is low, and RI has been identified to be weak when certain key routine activities are intensified.

Strategic Engagement of Technical Surge Capacity for Intensified Polio Eradication Initiative in Nigeria, 2012-2015.

BACKGROUND: Following the 65th World Health Assembly (WHA) resolution on intensification of the Global Poliomyelitis Eradication Initiative (GPEI), the Nigerian government, with support from the World Health Organization (WHO) and other partners, implemented a number of innovative strategies to curb the transmission of wild poliovirus (WPV) in the country. One of the innovations successfully implemented since mid 2012 is the WHO's engagement of surge capacity personnel. METHODS: The WHO reorganized its functional structure, adopted a transparent recruitment and deployment process, provided focused technical and management training, and applied systematic accountability framework to successfully manage the surge capacity project in close collaboration with the national counterparts and partners. The deployment of the surge capacity personnel was guided by operational and technical requirement analysis. RESULTS: Over 2200 personnel were engaged, of whom 92% were strategically deployed in 11 states classified as high risk on the basis of epidemiological risk analysis and compromised security. These additional personnel were directly engaged in efforts aimed at improving the performance of polio surveillance, vaccination campaigns, increased routine immunization outreach sessions, and strengthening partnership with key stakeholders at the operational level, including community-based organizations. DISCUSSION: Programmatic interventions were sustained in states in which security was compromised and the risk of polio was high, partly owing to the presence of the surge capacity personnel, who are engaged from the local community. Since mid-2012, significant programmatic progress was registered in the areas of polio supplementary immunization activities, acute flaccid paralysis surveillance, and routine immunization with the support of the surge capacity personnel. As of 19 June 2015, the last case of WPV was reported on 24 July 2014. The surge infrastructure has also been instrumental in building local capacity; supporting other public health emergencies, such as the Ebola outbreak response and measles and meningitis outbreaks; and strengthening the integrated disease surveillance and response. Due to weak health systems in the country, it is vital to maintain a reasonable level of the surge capacity for successful implementation of the 2013-2018 global polio endgame strategy and beyond.

Effectiveness of poliovirus vaccines against circulating vaccine-derived type 2 poliomyelitis in Nigeria between 2017 and 2022: a case-control study.

BACKGROUND: Between 2018 and 2022, Nigeria experienced continuous transmission of circulating vaccine-derived type 2 poliovirus (cVDPV2), with 526 cases of cVDPV2 poliomyelitis detected in total and approximately 180 million doses of monovalent type 2 oral poliovirus vaccine (mOPV2) and 450 million doses of novel type 2 oral poliovirus vaccine (nOPV2) delivered in outbreak response campaigns. Inactivated poliovirus vaccine (IPV) was introduced into routine immunisation in 2015, with a second dose added in 2021. We aimed to estimate the effectiveness of nOPV2 against cVDPV2 paralysis and compare nOPV2 effectiveness with that of mOPV2 and IPV. METHODS: In this retrospective case-control study, we used acute flaccid paralysis (AFP) surveillance data in Nigeria from Jan 1, 2017, to Dec 31, 2022, using age-matched, onset-matched, and location-matched cVDPV2-negative AFP cases as test-negative controls. We also did a parallel prospective study from March, 2021, using age-matched community controls from the same settlement as the cases. We included children born after May, 2016, younger than 60 months, for whom polio immunisation history (doses of OPV from campaigns and IPV) was reported. We estimated the per-dose effectiveness of nOPV2 against cVDPV2 paralysis using conditional logistic regression and compared nOPV2 effectiveness with that of mOPV2 and IPV. FINDINGS: In the retrospective case-control study, we identified 509 cVDPV2 poliomyelitis cases in Nigeria with case verification and paralysis onset between Jan 1, 2017, and Dec 31, 2022. Of these, 82 children were excluded for not meeting inclusion criteria, and 363 (85%) of 427 eligible cases were matched to 1303 test-negative controls. Cases reported fewer OPV and IPV doses than test-negative controls (mean number of OPV doses 5·9 [SD 4·2] in cases vs 6·7 [4·3] in controls; one or more IPV doses reported in 95 [26%] of 363 cases vs 513 [39%] of 1303 controls). We found low per-dose effectiveness of nOPV2 (12%, 95% CI -2 to 25) and mOPV2 (17%, 3 to 29), but no significant difference between the two vaccines (p=0·67). The estimated effectiveness of one IPV dose was 43% (23 to 58). In the prospective study, 181 (46%) of 392 eligible cases were matched to 1557 community controls. Using community controls, we found a high effectiveness of IPV (89%, 95% CI 83 to 93, for one dose), a low per-dose effectiveness of nOPV2 (-23%, -45 to -5) and mOPV2 (1%, -23 to 20), and no significant difference between the per-dose effectiveness of nOPV2 and mOPV2 (p=0·12). INTERPRETATION: We found no significant difference in estimated effectiveness of the two oral vaccines, supporting the recommendation that the more genetically stable nOPV2 should be preferred in cVDPV2 outbreak response. Our findings highlight the role of IPV and the necessity of strengthening routine immunisation, the primary route through which IPV is delivered. FUNDING: Bill & Melinda Gates Foundation and UK Medical Research Council.

Providing information for decision-making in the Nigerian Polio Eradication Program, 2016-2020.

Nigeria made a coordinated effort to be certified by the World Health Organization's African Region for interrupting endemic transmission of wild poliovirus type-1 (WPV1) in August 2020 as a response to the resurgence of WPV1 cases in August 2016 after going two years without a case. The NEOC Data Working Group (DWG) was instrumental in providing quality and timely surveillance and campaign information for decision-making in order to interrupt WPV1 transmission and provide data toward documentation of its elimination for regional certification. The polio pre-campaign dashboard was used to assess the level of preparedness for Oral Poliovirus Vaccine (OPV) polio supplementary immunization activities (SIA) at three weeks, two weeks, one week, and three days to the start of each campaign implemented during 2016-2020. The administrative tally sheet, independent monitoring survey, and Lot Quality Assurance Sampling (LQAS) survey data collected and shared from the implementation level were analyzed by the EOC DWG to provide information by person, place, and time. Using a 90% threshold in LQAS surveys defining quality SIAs, the proportion of Local Government Areas (LGAs) in Nigeria's states in which post-SIA LQAS surveys were conducted that met this threshold were assessed over time. The highest level of preparedness attained by 3 days to a polio campaign during August 2016-February 2020 was 95% and the lowest attained was 77%. The admin, independent monitoring, and LQAS data analysis results were given to EOC working groups for assessing the performance and quality of each campaign. Twenty-twenty five percent of LGAs that failed LQAS were identified for repeat vaccination. Further, acute flaccid paralysis and environmental surveillance data and laboratory results were analyzed and shared with NEOC and partners. The government and partners used the information generated by the Data Working Group to take evidence-based action including determining the scope of the polio campaign, intensification of surveillance and routine immunization activities, and special intervention activities. On average, 12% of the 774 LGAs were identified as polio high risk LGAs for intervention using selected surveillance, routine immunization (RI), SIAs, and other relevant data sets. National Emergency Operation Centre Data Working Group provided quality and timely information that supported decision-making processes for the polio program in Nigeria. The quality and timely information enabled the NEOC to make evidence-based and timely decisions that contributed to gap identification and decision-making.

Innovative strategies developed to mitigate the impact of COVID-19 pandemic on polio surveillance in Nigeria, 2020.

Introduction: following the spread of the COVID-19 pandemic to Nigeria, the Federal Government of Nigeria restricted human and vehicular movements to curb the spread of the disease. This action had a negative impact on Acute Flaccid Paralysis (AFP) surveillance, with a resultant reduction in the number of AFP cases reported. This paper describes the impact of the COVID-19 pandemic on poliovirus surveillance in Nigeria and the proactive interventions by Nigeria´s polio program to mitigate the impact of COVID-19 on polio surveillance. Methods: nine innovative strategies were implemented in all 774 Local Government Areas (LGA) of the 36 states and Federal Capital Territory (FCT) of the country. These strategies were developed by the national surveillance officers and operationalized by sub-national surveillance officers with different strategies starting at different epidemiological weeks from week 14 to 23, 2020. Many of the strategy innovations were technology-based and included: the use of mobile phones to send the AFP case definition and video by WhatsApp or by SMS, the use of state-specific toll-free numbers and Mobile Telephone Network (MTN) (mobile service provider) CallerfeelTM to community informants (CI) who were the main targets of the interventions to increase case detection and reporting. Others included the use of abridged e-surveillance integrated supportive supervision (ISS) checklists, virtual monthly DSNO meetings, and batched AFP stool specimen transportation network. Results: compared to the same period in 2019, the cumulative rate of AFP case detection and reporting had gradually declined from 39.1% in January to 16.7% before the commencement of the interventions in week 20, 2020. However, the detection and reporting increased by 57.% from week 20 to week 47 compared to the same period in 2019. This is because with COVID-19, hospital visitation dropped, and the sick remained in the communities, so the CI network was relied on to detect and report AFP cases. The cumulative proportion of AFP cases reported by community informants as of week 47 increased from 13% in 2018 to 21% in 2020. This indicates an increase of 38%. Thirty-five AFP cases were detected and reported using the MTN Caller Feel strategy, while 15 cases were reported through state-specific toll-free numbers. Conclusion: the implementation of the innovative strategies was able to mitigate the low AFP case detection and reporting observed at the initial stage of the COVID-19 pandemic. The use of technology facilitated reaching the CI network, which was more instrumental in detecting and reporting the cases.

Assessment of open data kit mobile technology adoption to enhance reporting of supportive supervision conducted for oral poliovirus vaccine supplementary immunization activities in Nigeria, March 2017-February 2020.

Introduction: in Nigeria, supportive supervision of Supplementary Immunization Activities (SIA) is a quality improvement strategy for providing support to vaccination teams administering the poliovirus vaccines to children under 5 years of age. Supervision activities were initially reported in paper forms. This had significant limitations, which led to Open Data Kit (ODK) technology being adopted in March 2017. A review was conducted to assess the impact of ODK for supervision reporting in place of paper forms. Methods: issues with paper-based reporting and the benefits of ODK were recounted. We determined the average utilization of ODK per polio SIA rounds and assessed the supervision coverage over time based on the proportion of local government areas with ODK geolocation data per round. Results: a total of 17 problematic issues were identified with paper-based reporting, and ODK addressed all the issues. Open Data Kit-based supervision reports increased from 3,125 in March 2017 to 51,060 in February 2020. Average ODK submissions for national rounds increased from 84 in March 2017 to 459 in February 2020 and for sub-national rounds increased from 533 in July 2017 to 1,596 in October 2019. Supportive supervision coverage improved from 42.5% in March 2017 to 97% in February 2020. Conclusion: the use of digital technologies in public health has comparative advantages over paper forms, and the adoption of ODK for supervision reporting during polio SIAs in Nigeria experienced the advantages. The visibility and coverage of supportive supervision improved, consequentially contributing to the improved quality of polio SIAs.

The role of polio emergency operations centers: perspectives for future disease control initiatives in Nigeria.

The Nigeria Polio Emergency Operations Centre (EOC) was established in October 2012 to strengthen coordination, provide strategic direction based on real-time data analysis, and manage all operational aspects of the polio eradication program. The establishment of seven state-level polio EOCs followed. With success achieved in the interruption of wild poliovirus (WPV) transmission as certified in 2020, the future direction of the polio EOC is under consideration. This paper describes the role of the polio EOC in other emergencies and perspectives on future disease control initiatives. A description of the functionality and operations of the polio EOC and a review of documentation of non-polio activities supported by the EOC was done. Key informant insights of national and state-level stakeholders were collected through an electronic questionnaire to determine their perspectives on the polio EOC's contributions and its future role in other public health interventions. The polio EOC structure is based on an incident management system with clear terms of reference and accountability and with full partner coordination. A decline in WPV1 cases was observed from 122 cases in 2012 to 0 in 2015; previously undetected transmission of WPV1 was confirmed in 2016 and all transmission was interrupted under the coordination of the EOCs at national and state levels. During 2014-2019, the polio EOC infrastructure and staff expertise were used to investigate and respond to outbreaks of Ebola, measles, yellow fever, and meningitis and to oversee maternal and neonatal tetanus elimination campaigns. The EOC structure at the national and state levels has contributed to the positive achievements in the polio eradication program in Nigeria and further in the coordination of other disease control and emergency response activities. The transition of the polio EOCs and their capacities to support other non-polio programs will contribute to harnessing the country's capacity for effective coordination of public health initiatives and disease outbreaks.

Determining Inaccurate Coordinates in Electronic Data Collection for Surveillance and Immunization Supportive Supervision: A Case Study of Nigeria EPI Supportive Supervision Module.

The mobile phone global positioning system (GPS) is used to reconnaissance a mobile phone user's location, e.g., at work, home, shops, etc. Such information can be used to feed data gathering expeditions, the actual position of the interviewer/surveyor using the mobile phone inert settings of location mode via GPS, WIFI, and Mobile networks. Mobile devices are becoming progressively erudite and now integrate diverse and robust sensors. The new generation of smartphones is multi-laden with sensors, including GPS sensors. The study describes and evaluates a data-gathering process used by the World Health Organization (WHO-Nigeria, EPI Program) that uses phone-based in-built GPS sensors to identify the position of users while they undergo supportive supervision. This form of spatial data is collected intrinsically using the Open Data Kit (ODK) GPS interface, which interlaces with the mobile phone GPS sensor to fetch the geo-coordinates during the process. It represents a step in building a methodology of matching places on the map with the geo-coordinates received from the mobile phones to investigate deviation patterns by devices and location mode. The empirical results can help us to understand the variation in geospatial data collation across devices and highlight critical criteria for choosing mobile phones for mobile surveys and data campaigns. This study reviewed the existing data gathered inadvertently from 10 brands of smartphones over 1 year of using the mobile data collection with over 80,000 field visits to predict the deviation pattern for spatial data acquisition via mobile phones by different brands.

Progress Towards Measles Elimination in Nigeria: 2012 - 2016.

INTRODUCTION: Nigeria has adopted the African Regional measles elimination targets and is implementing the recommended strategies. Nigeria provides routine measles vaccination for children aged 9 months. In addition, since 2006, Nigeria has been conducting nationwide measles supplemental Immunisation activities (SIAs) or mass vaccination campaigns every 2 years, and has established measles case-based surveillance. METHODS: We reviewed routine and supplemental measles immunization coverage data, as well as measles case-based surveillance data from Nigeria for the years 2012 - 2016, in an attempt to determine the country's progress towards these elimination targets. RESULTS: The first dose measles vaccination coverage in Nigeria ranged from 42% and 54% between 2012 and 2015, according to the WHO UNICEF national coverage estimates. Nigeria achieved 84.5% coverage by survey following the 2015 nationwide measles supplemental immunisation activities (SIAs). During this period, the incidence of confirmed measles ranged from 25 - 300 confirmed cases per million population per year, with the Northern States having significantly higher incidence as compared to the Southern States. At the same time, the pattern of confirmed cases indicated a consistent shift in epidemiological susceptibility including older age children. CONCLUSIONS: In order to accelerate its progress towards the measles elimination targets, Nigeria should build population immunity on a sustainable basis by addressing systemic issues in order to scale up routine immunisation coverage, especially in the Northern half of the country; tailoring the target age for measles SIAs so as to sharply reduce measles incidence in age groups heavily affected by the disease; effectively mobilising resources and improving the quality of planning and coverage outcome of SIAs.

Vaccine perception among acceptors and non-acceptors in Sokoto State, Nigeria.

Vaccine perceptions among acceptors and non-acceptors of childhood vaccination were explored. Seventy-two care givers, among them, acceptors and non-acceptors were interviewed in-depth with an interview guide that assessed vaccine acceptance, social and personality factors, and health belief model (HBM) categories in relation to oral polio vaccine (perceived susceptibility, severity, cost barriers, general barriers, benefits, knowledge, and engagement in preventative health behaviours). Community leaders were purposively selected while parents were selected on the basis of availability while ensuring the different attitude to vaccines was covered. Results showed that the HBM framework was found to be appropriate for identifying and distinguishing vaccine acceptors and non-acceptors. In addition, the HBM categories of benefits and susceptibility were found to influence oral polio vaccine acceptance. Second, the opinion of family members about the oral polio vaccine moderated the relationship between number of social ties and vaccine acceptance. Further, oral polio vaccine acceptance was related to outbreaks of paralysis of any sort, but not aggregate scores of other preventative health behaviours. Implications of this study include the investigation of vaccine acceptance in a high risk population. Research was done to investigate vaccine acceptance.