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.

Progress Toward Poliomyelitis Eradication - Nigeria, January 2018-May 2019.

The number of wild poliovirus (WPV) cases in Nigeria decreased from 1,122 in 2006 to six WPV type 1 (WPV1) in 2014 (1). During August 2014-July 2016, no WPV cases were detected; during August-September 2016, four cases were reported in Borno State. An insurgency in northeastern Nigeria had resulted in 468,800 children aged <5 years deprived of health services in Borno by 2016. Military activities in mid-2016 freed isolated families to travel to camps, where the four WPV1 cases were detected. Oral poliovirus vaccine (OPV) campaigns were intensified during August 2016-December 2017; since October 2016, no WPV has been detected (2). Vaccination activities in insurgent-held areas are conducted by security forces; however, 60,000 unvaccinated children remain in unreached settlements. Since 2018, circulating vaccine-derived poliovirus type 2 (cVDPV2) has emerged and spread from Nigeria to Niger and Cameroon; outbreak responses to date have not interrupted transmission. This report describes progress in Nigeria polio eradication activities during January 2018-May 2019 and updates the previous report (2). Interruption of cVDPV2 transmission in Nigeria will need increased efforts to improve campaign quality and include insurgent-held areas. Progress in surveillance and immunization activities will continue to be reviewed, potentially allowing certification of interruption of WPV transmission in Africa in 2020.

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.

Polio eradication in Nigeria: evaluation of the quality of acute flaccid paralysis surveillance documentation in Bauchi state, 2016.

BACKGROUND: Nigeria is the only country in Africa that is yet to be certified as polio free. Surveillance for acute flaccid paralysis (AFP) is the foundation of the polio eradication initiative since it provides information to alert both health managers and clinician that timely actions should be initiated to interrupt transmission of the polio virus. The strategy also provides evidence for the absence of wild poliovirus. This evaluation was performed to assess key quality indicators defined by the polio eradication program and thus to identify gaps to allow planning for corrective measures to achieve a polio-free situation in Bauchi state and in Nigeria at large. We conducted a cross-sectional descriptive study which involved a desk review of documents to authenticate the correctness and completeness of data, and a review of documented evidence for the quality of AFP surveillance. We interviewed Local Government Authority (LGA) surveillance officers and clinicians from focal and non-focal sites, along with caregivers of children with AFP and community leaders. The data were entered and analyzed in a Microsoft Excel spreadsheet. METHODS: We conducted a cross-sectional study of the AFP surveillance and documentation in eighteen of the twenty Local Government Areas (LGAs) of Bauchi State. We assessed the knowledge of the clinician at focal and non-focal sites on case definition of AFP, the number and method of stool specimen collection to investigate a case and types of training received for AFP surveillance. We verified AFP case investigations for the last three years: The caregivers (mothers) were interviewed to authenticate the reported information of AFP cases, the method used for stool specimen collection and feedbacks. Community leaders' knowledge on AFP surveillance was also assessed. Data was entered and analyzed in excel spread sheet. RESULTS: Of the 18 LGA Disease Surveillance and Notification Officers (DSNOs), only 2 (11%) and 5 (28%) had reports of polio outbreak investigations and supervisory visits at the lower levels, respectively. Furthermore, only 6 (33%) and 7 (39%) of the DSNOs had minutes of meetings and surveillance work plans, respectively. Of the 31 AFP cases investigated, only 39, 26, 23, and 23% had correct and complete information for the birth day, birth month, date of onset of paralysis, and date of investigation, respectively. Seventy-one percent of the clinicians at the AFP focal sites knew the correct definition for AFP compared with only 30% at the non-focal sites. Of the 38 caregivers (mothers), 16 (42%) did not remember the day or month the AFP investigation was conducted. However, 95% gave a correct number of stool samples collected and 40% mentioned that the samples were collected 24 h apart. Feedback was not given to 26 (68%) of the caregivers. The majority (79%) of the community leaders knew how to recognize a case of AFP and knew that the stool was the specimen required for the investigation, but 21% did not know to whom they should report a case of AFP in their community. CONCLUSION: This study revealed a gap in the quality indicators for polio eradication in the state, especially regarding knowledge and documentation for AFP surveillance at the operational level. Regular training of the DSNOs and focal persons, regular sensitization of clinicians, community education, supplies of reporting tools, and ensuring their judicious use will improve AFP surveillance in the state.

Mobilizing political support proved critical to a successful switch from tOPV to bOPV in Kano, Nigeria 2016.

BACKGROUND: Kano is one of the high-risk states for polio transmission in Northern Nigeria. The state reported more cases of wild polioviruses (WPVs) than any other state in the country. The Nigeria Demographic and Health Survey of 2013 indicated that OPV3 coverage in the routine immunization (RI) programmewas 57.9%. Additionally, serial polio seroprevalence studies conducted from 2011 to 2015 in the eightmetropolitan LGAs indicated low immunity levels against all three polio serotypes in children below one year. Areas with sub-optimal RI coverage such as Kanothat fail to remove all tOPV during the tOPV-bOPV switchwill be at increased risk of VDPV2 circulation. METHODS: We assessed the impact of political leadership engagement in mobilizing other stakeholders on the outcomes of the bOPV-tOPV switch in Kano State from February to May 2016 using nationally-selected planning and outcome indicators. RESULTS: A total of 670 health facilities that provide RI services were assessed during the pre-switch activities. Health workers were aware of the switch exercise in 520 (95.1%) of the public health facilities assessed. It was found that health workers knew what to do should tOPV be found in any of the 521 (95.2%)public health facilities assessed. However, there was a wide disparity between the public and private health practitioners' knowledge on basic concepts of the switch. There was 100% withdrawal of tOPV from the state and the seven zonal cold stores. Unmarked tOPVwas found in the cold chain system in 2 (4.5%) LGAs. Only one health facility (0.8%) had tOPV in the cold chain. No tOPVwas identified outside the cold chain without the "Do not use" sticker in any of the health facilities. CONCLUSION: The engagement of the political leadership to mobilize other key stakeholders facilitated successful implementation of the tOPV-bOPVswitch exercise and provided opportunity to strengthen partnerships with the private health sector in Kano State.

Stopping circulatory vaccine-derived poliovirus in Kaduna state by scaling up special interventions in local government areas along rivers of interest- kamacha basin experience, 2013-2015.

BACKGROUND: The Kamacha river is one of the five polio environmental surveillance sites in Kaduna State where 13 circulating vaccine-derived polioviruses (cVDPDs) were isolated between 2014 and 2015. Kamacha river accounted for 5 of all reported cVDPVs in Kaduna State between 2014 and 2015. Poor quality Supplemental Immunization Activities (SIAs) and low population immunity have been reported in the 10 LGAs with tributaries that flow into the river. We described the processes of implementing the various health interventions in these targeted LGAs along the Kamacha River and assessed the effectiveness of the interventions in stopping cVDPV in Kaduna, state, Nigeria. METHODS: Special interventions that had been proven to be functional and effective in reaching unreached children with potent vaccines in the state were scaled up in these targeted 10 LGAs along the Kamacha River. These interventions included revision of house based microplans, scaling up of transit vaccination, scaling up of youth engagement, intensified supportive supervision, scaling up of Directly Observed Polio Vaccination (DOPV) and in-between rounds vaccination activities. We analyzed immunization plus days (IPDs) administrative tally sheet and monitoring data from 10 rounds before and 10 rounds after the special interventions. RESULTS: The number of children immunized increased from 1,862,958 in December 2014 before the intervention to 1,922,940 in March 2016 after the intervention. Lot Quality Assurance Sampling (LQAS) results showed an increase in the proportion of LGAs accepted at coverage > 90% after the interventions, from 67% before intervention to 84% after intervention. The proportion of non-polio AFP children with > 4 doses of oral polio vaccine increased from 2 to 8% before to 93-98% after the interventions.. No new environmental cVDPV has been isolated since the introduction of the interventions in April 2015 until July 2016. CONCLUSION: Scaling up known working interventions in the 10 LGAs with tributaries that drain to Kamacha River environmental sample site may have contributed to improved immunity and interruption of cVDPV in Kaduna state. These interventions should be replicated in LGAs and states with persistent poliovirus isolation.

Impact of engaging security personnel on access and polio immunization outcomes in security-inaccessible areas in Borno state, Nigeria.

BACKGROUND: Nigeria was polio free for almost 2 years but, with the recent liberation of areas under the captivity of insurgents, there has been a resurgence of polio cases. For several years, these inaccessible areas did not have access to vaccination due to activities of Bokoharam, resulting in a concentration of a cohort of unvaccinated children that served as a polio sanctuary. This article describes the processes of engagement of security personnel to access security-compromised areas and the impact on immunization outcomes. METHODS: We assessed routine program data from January 2016 to July 2016 in security-inaccessible areas and we evaluated the effectiveness of engaging security personnel to improve access to settlements in security-compromised Local Government Areas (LGAs) of Borno state. We thereafter evaluated the effects of this engagement on postcampaign evaluation indicators. RESULTS: From 15 LGAs accessible to vaccination teams in January 2016, there was a 47% increase in July 2016. The number of wards increased from 131 in January to 162 in July 2016, while the settlement numbers increased from 6050 in January to 6548 in July 2016. The average percentage of missed children decreased from 8% in January to 3% in July 2016, while the number of LGAs with ≥ 80% coverage increased from 85% in January to 100% in July 2016. CONCLUSION: The engagement of security personnel in immunization activities led to an improved access and improvement in postcampaign evaluation indicators in security-compromised areas of a Nigerian state. This approach promises to be an impactful innovation in reaching settlements in security-compromised areas.

Targeting the last polio sanctuaries with Directly Observed Oral Polio Vaccination (DOPV) in northern Nigeria, (2014-2016).

BACKGROUND: The declaration of poliomyelitis eradication as a programmatic emergency for global public health by the 65th World Health Assembly in 2012 necessitated innovations and strategies to achieve results. Review of the confirmed polio cases in 2013 showed that most of the cases were from non-compliant households, where parents connived with vaccinators to finger mark the children without actually vaccinating the children with oral polio vaccine or children were absent from home at the time of the visit of vaccinators. METHODS: We used pre-post design to quantify the outcomes of directly observed vaccination in 90 local government areas from 12 northern Nigeria states at very high risk of polio transmission. The strategy is an intervention, vaccinating children under the direct supervision of an independent supervisor to ensure compliance. Attractive incentives (pluses) were used to make parents willingly submit their children for vaccination or directly attract children to the vaccination teams or post as part of this strategy. RESULTS: There was a steady increase in population immunity in all the 90 DOPV implementing LGAs since the introduction of DOPV in 2013. The number of states in which > 90% of children received > 4 OPV doses increased from 7 in 2013 to 11 states by July 2016. Yobe state reported the highest proportional increase from 75 to 99% by July 2016 (22% increase), while Kano state reported 17% increase, from 82 to 99% by July 2016. CONCLUSION: Directly observed polio vaccination strategy improved uptake of polio vaccines and population immunity in high-risk areas for polio transmission.

Conduct of vaccination in hard-to-reach areas to address potential polio reservoir areas, 2014-2015.

BACKGROUND: The Global Vaccine Action Plan (GVAP) seeks to achieve the total realization of its vision through equitable access to immunization as well as utilizing the immunization systems for delivery of other primary healthcare programs. The inequities in accessing hard-to-reach areas have very serious implications for the prevention and control of vaccine-preventable diseases, especially the polio eradication initiative. The Government of Nigeria implemented vaccination in hard-to-reach communities with support from the World Health Organization (WHO) to address the issues of health inequities in the hard-to-reach communities. This paper documents the process of conducting integrated mobile vaccination in these hard-to-reach areas and the impact on immunization outcomes. METHODS: We conducted vaccination using mobile health teams in 2311 hard-to-reach settlements in four states at risk of sustaining polio transmission in Nigeria from July 2014 to September 2015. RESULTS: The oral polio vaccine (OPV)3 coverage among children under 1 year of age improved from 23% at baseline to 61% and OPV coverage among children aged 1-5 years increased from 60 to 90%, while pentavalent vaccine (penta3) coverage increased from 22 to 55%. Vitamin A was administered to 78% of the target population and 9% of children that attended the session were provided with treatment for malaria. CONCLUSIONS: The hard-to-reach project has improved population immunity against polio, as well as other routine vaccinations and delivery of child health survival interventions in the hard-to-reach and underserved communities.

Youth Group Engagement in Noncompliant Communities During Supplemental Immunization Activities in Kaduna, Nigeria, in 2014.

INTRODUCTION: One of the major challenges being faced in the Global Polio Eradication Initiative program is persistent refusal of oral polio vaccine (OPV) and harassment of vaccination team members by youths. The objective of the study was to describe the strategy of collaborating with recognized youth groups to reduce team harassment during vaccination campaigns and improve vaccination coverage in noncompliant communities. METHODS: We assessed data from polio vaccination activities in OPV-refusing communities in the Igabi and Zaria local government areas (LGAs) of Kaduna State in Nigeria. We evaluated the following factors to determine trends: enhanced independent monitoring data on the proportion of children missed by vaccination activities (hereafter, "missed children"), lot quality assurance surveys, and vaccination team harassment. RESULTS: The proportion of missed children decreased in both LGAs after the intervention. In Igabi LGA and Zaria LGA, the lowest proportions of missed children before and after the intervention decreased from 7% to 2% and from 5% to 1%, respectively. Lot quality assurance survey trends showed an improvement in immunization coverage 1 year after youth groups' engagement in both LGAs. CONCLUSIONS: Systematic engagement of youth groups has a great future in polio interruption as we approach the endgame strategy for polio eradication. It promises to be a veritable innovation in reaching chronically missed children in OPV-refusing communities.

The Journalists Initiatives on Immunisation Against Polio and Improved Acceptance of the Polio Vaccine in Northern Nigeria 2007-2015.

BACKGROUND: The polio eradication initiative had major setbacks in 2003 and 2007 due to media campaigns in which renowned scholars and Islamic clerics criticized polio vaccines. The World Health Organization (WHO) partnered with journalists in 2007 to form the Journalists Initiatives on Immunisation Against Polio (JAP), to develop communication initiatives aimed at highlighting polio eradication activities and the importance of immunization in northern Nigeria. METHODS: We evaluated the impact of JAP activities in Kaduna State by determining the total number of media materials produced and the number of newspaper clips and bulletins published in support of polio eradication. We also determined the number of households in noncompliant communities that became compliant with vaccination during 2015 supplementary immunization activities (SIAs) after JAP interventions and compared caregivers' sources of information about SIAs in 2007 before and after the JAP was formed. RESULTS: Since creation of the JAP, >500 reports have been published and aired, with most portraying polio vaccine positively. During June 2015 SIAs in high-risk wards of Kaduna STATE, JAP interventions resulted in vaccination of 5122 of 5991 children (85.5%) from noncompliant households. During early 2007, the number of caregivers who had heard about SIA rounds from the media increased from 26% in January, before the JAP was formed, to 33% in March, after the initiation of JAP activities. CONCLUSIONS: The formation of the JAP resulted in measurable improvement in the acceptance of polio vaccine in northern Nigeria.

Demand Creation for Polio Vaccine in Persistently Poor-Performing Communities of Northern Nigeria: 2013-2014.

INTRODUCTION: Poliomyelitis remains a global threat despite availability of oral polio vaccine (OPV), proven to reduce the burden of the paralyzing disease. In Nigeria, children continue to miss the opportunity to be fully vaccinated, owing to factors such as unmet health needs and low uptake in security-compromised and underserved communities. We describe the implementation and evaluation of several activities to create demand for polio vaccination in persistently poor-performing local government areas (LGAs). METHODS: We assessed the impact of various polio-related interventions, to measure the contribution of demand creation activities in 77 LGAs at very high risk for polio, located across 10 states in northern Nigeria. Interventions included provision of commodities along with the polio vaccine. RESULTS: There was an increasing trend in the number of children reached by different demand creation interventions. A total of 4 819 847 children were vaccinated at health camps alone. There was a reduction in the number of wards in which >10% of children were missed by supplementary immunization activities due to noncompliance with vaccination recommendations, a rise in the proportion of children who received ≥4 OPV doses, and a decrease in the proportion of children who were underimmunized or unimmunized. CONCLUSIONS: Demand creation interventions increased the uptake of polio vaccines in persistently poor-performing high-risk communities in northern Nigeria during September 2013-November 2014.

Revised Household-Based Microplanning in Polio Supplemental Immunization Activities in Kano State, Nigeria. 2013-2014.

BACKGROUND: Remarkable progress had been made since the launch of the Global Polio Eradication Initiative in 1988. However endemic wild poliovirus transmission in Nigeria, Pakistan, and Afghanistan remains an issue of international concern. Poor microplanning has been identified as a major contributor to the high numbers of chronically missed children. METHODS: We assessed the contribution of the revised household-based microplanning process implemented in Kano State from September 2013 to April 2014 to the outcomes of subsequent polio supplemental immunization activities using used preselected planning and outcome indicators. RESULTS: There was a 38% increase in the number of settlements enumerated, a 30% reduction in the number of target households, and a 54% reduction in target children. The reported number of children vaccinated and the doses of oral polio vaccine used during subsequent polio supplemental immunization activities showed a decline. Postvaccination lot quality assurance sampling and chronically missed settlement reports also showed a progressive reduction in the number of children and settlements missed. CONCLUSIONS: We observed improvement in Kano State's performance based on the selected postcampaign performance evaluation indicators and reliability of baseline demographic estimates after the revised household-based microplanning exercise.

Progress Toward Poliomyelitis Eradication--Nigeria, January 2014-July 2015.

Since the 1988 launch of global poliomyelitis eradication efforts, four of the six World Health Organization (WHO) regions have been certified polio-free. Nigeria is one of only three countries, along with Afghanistan and Pakistan, where transmission of wild poliovirus (WPV) has never been interrupted. During 2003-2013, northern Nigeria served as a reservoir for WPV reintroduction into 26 previously polio-free countries. In 2012, the Nigerian government launched a national polio eradication emergency plan to intensify efforts to interrupt WPV transmission. This report describes polio eradication activities and progress in Nigeria during January 2014-July 2015 and updates previous reports. No WPV cases have been reported to date in 2015, compared with a total of six cases reported during 2014. Onset of paralysis in the latest reported WPV type 1 (WPV1) case was July 24, 2014. Only one case of circulating vaccine-derived poliovirus type 2 (cVDPV2) has been reported to date in 2015, compared with 20 cVDPV2 cases during the same period in 2014. Pending final laboratory testing of 218 remaining specimens of 16,617 specimens collected since January 2015, Nigeria could be removed from the WHO list of polio-endemic countries in September 2015. Major remaining challenges to the national polio eradication program include sustaining political support and program funding in the absence of active WPV transmission, maintaining high levels of population immunity in hard-to-reach areas, and accessing children in security-compromised areas of the northeastern states.

Progress toward poliomyelitis eradication in Nigeria.

BACKGROUND: Transmission of wild poliovirus (WPV) has never been interrupted in Afghanistan, Pakistan, and Nigeria. Since 2003, infections with WPV of Nigerian origin have been detected in 25 polio-free countries. In 2012, the Nigerian government created an emergency operations center and implemented a national emergency action plan to eradicate polio. The 2013 revision of this plan prioritized (1) improving the quality of supplemental immunization activities (SIAs), (2) implementing strategies to reach underserved populations, (3) adopting special approaches in security-compromised areas, (4) improving outbreak response, (5) enhancing routine immunization and activities implemented between SIAs, and (6) strengthening surveillance. This report summarizes implementation of these activities during a period of unprecedented insecurity and violence, including the killing of health workers and the onset of a state of emergency in the northeast zone. METHODS: This report reviews management strategies, innovations, trends in case counts, vaccination and social mobilization activities, and surveillance and monitoring data to assess progress in polio eradication in Nigeria. RESULTS: Nigeria has made significant improvements in the management of polio eradication initiative (pei) activities with marked improvement in the quality of SIAs, as measured by lot quality assurance sampling (LQAS). Comparing results from February 2012 with results from December 2013, the proportion of local government areas (LGAs) conducting LQAS in the 11 high-risk states at the ≥90% pass/fail threshold increased from 7% to 42%, and the proportion at the 80%-89% threshold increased from 9% to 30%. During January-December 2013, 53 polio cases were reported from 26 LGAs in 9 states in Nigeria, compared with 122 cases reported from 13 states in 2012. No cases of WPV type 3 infection have been reported since November 2012. In 2013, no polio cases due to any poliovirus type were detected in the northwest sanctuaries of Nigeria. In the second half of 2013, WPV transmission was restricted to Kano, Borno, Bauchi, and Taraba states. Despite considerable progress, 24 LGAs in 2012 and 7 LGAs in 2013 reported ≥2 cases, and WPV continued to circulate in 8 LGAs that had cases in 2012. Campaign activities were negatively impacted by insecurity and violence in Borno and Kano states. CONCLUSIONS: Efforts to interrupt transmission remain impeded by poor SIA implementation in localized areas, anti-polio vaccine sentiment, and limited access to vaccinate children because of insecurity. Sustained improvement in SIA quality, surveillance, and outbreak response and special strategies in security-compromised areas are needed to interrupt WPV transmission in 2014.

Progress toward poliomyelitis eradication--Nigeria, January 2013-September 2014.

In 1988, the World Health Assembly resolved to interrupt wild poliovirus (WPV) transmission worldwide. By 2013, only three countries remained that had never interrupted WPV transmission: Afghanistan, Nigeria, and Pakistan. Since 2003, northern Nigeria has been a reservoir for WPV reintroduction into 26 previously polio-free countries. In May 2014, the World Health Organization declared the international spread of polio a Public Health Emergency of International Concern. Nigeria's main strategic goal is to interrupt WPV type 1 (WPV1) transmission by the end of 2014, which is also a main objective of the Global Polio Eradication Initiative's Polio Eradication and Endgame Strategic Plan for 2013-2018. This report updates previous reports (4-6) and describes polio eradication activities and progress in Nigeria during January 2013-September 30, 2014. Only six WPV cases had been reported in 2014 through September 30 compared with 49 reported cases during the same period in 2013. The quality of supplemental immunization activities (SIAs) improved during this period; the proportion of local government areas (LGAs) within 11 high-risk states with estimated oral poliovirus vaccine (OPV) campaign coverage at or above the 90% threshold increased from 36% to 67%. However, the number of reported circulating vaccine-derived poliovirus type 2 (cVDPV2) cases increased from four in 2013 to 21 to date in 2014, and surveillance gaps are suggested by genomic sequence analysis and continued detection of WPV1 by environmental surveillance. Interrupting all poliovirus circulation in Nigeria is achievable with continued attention to stopping cVDPV2 transmission, improving the quality of acute flaccid paralysis (AFP) surveillance, increasing vaccination coverage by strengthened routine immunization services, continuing support from all levels of government, and undertaking special initiatives to provide vaccination to children in conflict-affected areas in northeastern Nigeria.

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.

Micro-planning for immunization in Kaduna State, Nigeria: Lessons learnt, 2017.

BACKGROUND: The OPV 3 coverage for Kaduna State, 12-23 months old children was 34.4%. The low OPV 3 coverage, due mainly to weak demand for routine antigens and the need to rapidly boost population immunity against the disabling Wild Polio Virus (WPV), led the Global Polio Eradication Initiatives (GPEI) to increase supplemental OPV campaigns in Kaduna State, despite the huge cost and great burden on personnel. The OPV campaigns, especially in high risk (low vaccine uptake, <80% OPV 3 coverage and high vaccines refusal rate) states of northern Nigeria with poliovirus transmission has resulted in overestimated denominators or target population, as the highest ever vaccinated is used to set OPV campaign targets. METHODS: We utilized a cross-sectional study that assessed the impacts and possible solutions to the challenges of overestimated denominators in immunization services planning, delivery and performance evaluation in Kaduna State, Nigeria. We used both descriptive and quantitative approaches. We enumerated households and obtained the target populations for routine immunization (<1 year), polio campaign (<5 years) and acute flaccid paralysis surveillance (<15 years). RESULTS: We found a significant difference in mean scores between the micro-planning and supplemental vaccination data on a number of <5 years (M = 102967, SD = 62405, micro-planning compared to M = 157716, SD = 72212, supplemental vaccination, p < 0.05). We also found a significant difference in mean scores between the micro-planning and projected census data on a number of <1 year (M = 26128, SD = 16828, micro-planning compared to M = 14154, SD = 4894, census, p < 0.05). CONCLUSION: Periodic household-based micro-planning, aided with the use of technology for validation remains a useful tool in addressing gaps in immunization planning, delivery and performance evaluation in developing countries, such as Nigeria with overestimated denominators.