Pilot implementation of a routine immunization module of the district health information system version 2 in Kano State, Nigeria, 2014 - 2015.

Introduction: Timely and accurate data are necessary for informing sound decision-making and developing effective routine immunization (RI) programs. We launched a pilot project in Kano State to strengthen routine immunization (RI) data reporting through the immunization module of the District Health Information System version 2 (DHIS2). We examined the completeness and timeliness of reporting monthly RI data one year before and one year after DHIS2 module pilot in the State. Methods: The first phase of the DHIS2 RI module pilot in Kano included training on RI data tools in November 2014 and in January 2015 for 36 state and zonal personnels, 276 local government area (LGA) personnel, and 2,423 health facility (HF) staff. A RI-focused dashboard to display core RI accountability framework indicators, such as completeness and timeliness of reporting, planned immunization sessions conducted, coverage and dropout was implemented. Report completeness was ratio of submitted reports to number of health facilities while report timeliness was ratio of reports on the DHIS2 by 14th of the month to number of expected. Results: Completeness of data reporting increase from 70% in 2014 to 87% in 2015, while timeliness of reporting increase from 64% to 87% over the same period. Challenges encountered during the implementation process included limited access to internet, power outages, health workers strike, staff attrition and competing state activities. Conclusion: The pilot implementation of the DHIS2 immunization module in Kano State led to modest improvement in the reporting of RI services. Several lessons learned were used to guide scale-up to other states in the country.

Revelation of an important weakness in polio elimination efforts in Nigeria: a descriptive cross-sectional study of nomadic dynamics in Sokoto and Taraba States, May 2013.

Introduction: Operational gaps in the Global Polio Eradication Initiative implementation had been partly responsible for inadequate population immunity and the continued transmission of wild poliovirus in Nigeria before the African Region was declared polio-free in 2020. Missed opportunities to provide services in nomadic populations due to frequent mobility, lack of inclusion in microplans and the remoteness of their settlements were the major challenges. During May 2013 we conducted immunization outreach to nomadic and other underserved communities in Rabah LGA, Sokoto state, and Ardo Kola LGA, Taraba state, in Nigeria to identify and vaccinate children missed during supplemental immunization activities while identifying missed acute flaccid paralysis cases. Methods: An enumeration checklist and data collection instruments on Android cell phones were used to capture socio-demographic data and GPS coordinates on nomadic settlements, households, number of children aged <5 years, children previously missed for vaccination and their locations. Local guides led trained enumerators to underserved communities for the enumeration and vaccination. Data were analyzed using Microsoft Excel 2007. Results: A total of 324 settlements were listed for the two states, and 111 (34.3%) of these were identified as missed when compared with micro-planning for the most recent SIA. In these settlements, 3,533 households and 9,385 children aged <5 years were listed. We administered oral poliovirus vaccine to all 1,946 missed children during the recent or any supplemental immunization activities. Of these, 527 (27.1%) had never been vaccinated. We found no missed acute flaccid paralysis cases. Conclusion: Nomadic populations continue to be underserved, especially for vaccination services. This results in pockets of populations with low herd immunity and increased risk for poliovirus transmission. Community leaders and nomadic settlements should be included in the micro-planning of all supplemental immunization activities to ensure all children receive vaccination services.

Enhancing acute flaccid paralysis surveillance through the use of pictorial surveillance reminder cards during supplementary immunization activities, December 2014: a survey in Jigawa State, Nigeria.

Introduction: Acute flaccid paralysis (AFP) pictorial surveillance reminder cards (AFP cards) could aid AFP case identification during supplementary immunization activities (SIAs). We assessed the availability and utilization of AFP cards among vaccination teams during the December 2014 polio SIAs in Jigawa State, Nigeria. Methods: We conducted a cross-sectional survey of a convenience sample of 95 vaccination team supervisors. We used a semi-structured interviewer-administered questionnaire to collect information on socio-demographics, knowledge of AFP cases, availability and utilization of the AFP cards for case identification and investigation and non-compliance resolution by vaccination teams. Univariate and bivariate analyses were performed using Epi Info version 3.5.1. Results: Of the 95 supervisors interviewed, 86 (91%) reported that vaccinators properly displayed the AFP cards, 90 (95%) reported use of cards for AFP case identification, 88 (93%) reported use of cards to resolve non-compliance with polio vaccination and 77 (81%) reported use of cards to ask caregivers six key questions to prevent missed children. Fifty-eight (61%) supervisors knew the AFP case definition. A total of 21 possible AFP cases were identified by vaccination team members with the aid of the cards, of which 17 (81%) were referred to the nearest health facility. Conclusion: The survey demonstrated usefulness of reminder cards for identification and follow-up of AFP cases. Based on these findings, use of AFP cards was implemented in all Nigerian States and similar cards were developed and implemented for measles surveillance during SIAs.

Strengthening facility-based immunization service delivery in local government areas at high risk for polio in Northern Nigeria, 2014-2015.

Introduction: The National Stop Transmission of Polio (NSTOP) program was created in 2012 to support the Polio Eradication Initiative (PEI) in Local Government Areas (LGAs) at high risk for polio in Northern Nigeria. We assessed immunization service delivery prior to the commencement of NSTOP support in 2014 and after one year of implementation in 2015 to measure changes in the implementation of key facility-based Routine Immunization (RI) components. Methods: The pre- and post-assessment was conducted in selected health facilities (HFs) in 61 LGAs supported by NSTOP in 5 states. A standardized questionnaire was administered to the LGA and HF immunization staff by trained interviewers on key RI service delivery components. Results: At the LGA level, an increase was observed in key components including availability of updated Reach Every Ward (REW) micro-plans with identification of hard to reach settlements (65.6% baseline, 96.8% follow-up, PR = 1.5 (95% CI 3.4 - 69.8), vaccine forecasting (77.1% baseline, 93.5% follow-up, PR =1.2 (95% CI 1.8 - 13.8), and timely delivery of monthly immunization reports (73.8% baseline, 90.2% follow-up; PR =1.2 (95% CI 1.2 - 9.0). At the HF level, there was an increase in percentage of HFs with written supervisory feedback (44.5% baseline, 82.5% follow-up, PR = 1.8 (95% CI 4.7 - 7.3), written stock records (66.5% baseline, 87.9% follow-up, PR = 1.3 (95% CI 2.9 - 4.7) and updated immunization monitoring charts (76.3% baseline, 95.6% follow-up, PR = 1.3 (95% CI 4.6 - 9.9). Conclusion: We observed an improvement in key RI service delivery components following implementation of NSTOP program activities in supported LGAs.

Building a new platform to support public health emergency response in Africa: the AFENET Corps of Disease Detectives, 2018-2019.

Public health emergency (PHE) response in sub-Saharan Africa is constrained by inadequate skilled public health workforce and underfunding. Since 2005, the African Field Epidemiology Network (AFENET) has been supporting field epidemiology capacity development and innovative strategies are required to use this workforce. In 2018, AFENET launched a continental rapid response team: the AFENET Corps of Disease Detectives (ACoDD). ACoDD comprises field epidemiology graduates and residents and was established to support PHE response. Since 2018, AFENET has deployed the ACoDD to support response to several PHEs. The main challenges faced during ACoDD deployments were financing of operations, ACoDD safety and security, resistance to interventions and distrust of the responders by some communities. Our experience during these deployments showed that it was feasible to mobilise and deploy ACoDD within 48 hours. However, the sustainability of deployments will depend on establishing strong linkages with the employers of ACoDD members. PHEs are effectively controlled when there is a fast deployment and strong linkages between the stakeholders. There are ongoing efforts to strengthen PHE preparedness and response in sub-Saharan Africa. ACoDD members are a competent workforce that can effectively augment PHE response. ACoDD teams mentored front-line health workers and community health workers who are critical in PHE response. Public health emergence response in sub-Saharan Africa is constrained by inadequacies in a skilled workforce and underfunding. ACoDD can be utilised to overcome the challenges of accessing a skilled public health workforce. To improve health security in sub-Saharan Africa, more financing of PHE response is needed.

Using Acute Flaccid Paralysis Surveillance as a Platform for Vaccine-Preventable Disease Surveillance.

Surveillance for acute flaccid paralysis (AFP) is a fundamental cornerstone of the global polio eradication initiative (GPEI). Active surveillance (with visits to health facilities) is a critical strategy of AFP surveillance systems for highly sensitive and timely detection of cases. Because of the extensive resources devoted to AFP surveillance, multiple opportunities exist for additional diseases to be added using GPEI assets, particularly because there is generally 1 district officer responsible for all disease surveillance. For this reason, integrated surveillance has become a standard practice in many countries, ranging from adding surveillance for measles and rubella to integrated disease surveillance for outbreak-prone diseases (integrated disease surveillance and response). This report outlines the current level of disease surveillance integration in 3 countries (Nepal, India, and Nigeria) and proposes that resources continue for long-term maintenance in resource-poor countries of AFP surveillance as a platform for surveillance of vaccine-preventable diseases and other outbreak-prone diseases.

Approaches to Vaccination Among Populations in Areas of Conflict.

Vaccination is an important and cost-effective disease prevention and control strategy. Despite progress in vaccine development and immunization delivery systems worldwide, populations in areas of conflict (hereafter, "conflict settings") often have limited or no access to lifesaving vaccines, leaving them at increased risk for morbidity and mortality related to vaccine-preventable disease. Without developing and refining approaches to reach and vaccinate children and other vulnerable populations in conflict settings, outbreaks of vaccine-preventable disease in these settings may persist and spread across subnational and international borders. Understanding and refining current approaches to vaccinating populations in conflict and humanitarian emergency settings may save lives. Despite major setbacks, the Global Polio Eradication Initiative has made substantial progress in vaccinating millions of children worldwide, including those living in communities affected by conflicts and other humanitarian emergencies. In this article, we examine key strategic and operational tactics that have led to increased polio vaccination coverage among populations living in diverse conflict settings, including Nigeria, Somalia, and Pakistan, and how these could be applied to reach and vaccinate populations in other settings across the world.

Continued Endemic Wild Poliovirus Transmission in Security-Compromised Areas - Nigeria, 2016.

On August 10, 2016, 2 years after the most recent wild poliovirus (WPV) case was reported in Nigeria (in July 2014) (1), two WPV cases were reported in the northeastern state of Borno, which has been severely affected by insurgency-related insecurity since 2013. On September 9 and 26, 2016, two additional WPV cases were reported in Borno in children whose families migrated from security-compromised, inaccessible areas of the state. All four cases were WPV serotype 1 (WPV1), with genetic differences indicating prolonged undetected transmission. A large-scale emergency response plan was developed and implemented. The plan initially called for vaccination of 815,791 children during August 15-18 in five local government areas (LGAs) in the immediate vicinity of the first two WPV cases. Subsequently, the plan was expanded to regionally synchronized supplementary immunization activities (SIAs), conducted during August 27-December 6 in five Lake Chad basin countries at increased risk for national and regional WPV1 transmission (Cameroon, Central African Republic, Chad, Niger, and Nigeria). In addition, retrospective searches for missed cases of acute flaccid paralysis (AFP), enhanced environmental surveillance for polioviruses, and polio surveillance system reviews were conducted. Prolonged undetected WPV1 transmission in Borno State is a consequence of low population immunity and severe surveillance limitations associated with insurgency-related insecurity and highlights the risk for local and international WPV spread (2). Increasing polio vaccination coverage and implementing high-quality polio surveillance, especially among populations in newly secured and difficult-to-access areas in Borno and other Lake Chad basin areas are urgently needed.

Routine Vaccination Coverage in Northern Nigeria: Results from 40 District-Level Cluster Surveys, 2014-2015.

BACKGROUND: Despite recent success towards controlling poliovirus transmission, Nigeria has struggled to achieve uniformly high routine vaccination coverage. A lack of reliable vaccination coverage data at the operational level makes it challenging to target program improvement. To reliably estimate vaccination coverage, we conducted district-level vaccine coverage surveys using a pre-existing infrastructure of polio technical staff in northern Nigeria. METHODS: Household-level cluster surveys were conducted in 40 polio high risk districts of Nigeria during 2014-2015. Global positioning system technology and intensive supervision by a pool of qualified technical staff were used to ensure high survey quality. Vaccination status of children aged 12-23 months was documented based on vaccination card or caretaker's recall. District-level coverage estimates were calculated using survey methods. RESULTS: Data from 7,815 children across 40 districts were analyzed. District-level coverage with the third dose of diphtheria-pertussis-tetanus vaccine (DPT3) ranged widely from 1-63%, with all districts having DPT3 coverage below the target of 80%. Median coverage across all districts for each of eight vaccine doses (1 Bacille Calmette-Guérin dose, 3 DPT doses, 3 oral poliovirus vaccine doses, and 1 measles vaccine dose) was <50%. DPT3 coverage by survey was substantially lower (range: 28%-139%) than the 2013 administrative coverage reported among children aged <12 months. Common reported reasons for non-vaccination included lack of knowledge about vaccines and vaccination services (50%) and factors related to access to routine immunization services (15%). CONCLUSIONS: Survey results highlighted vaccine coverage gaps that were systematically underestimated by administrative reporting across 40 polio high risk districts in northern Nigeria. Given the limitations of administrative coverage data, our approach to conducting quality district-level coverage surveys and providing data to assess and remediate issues contributing to poor vaccination coverage could serve as an example in countries with sub-optimal vaccination coverage, similar to Nigeria.

Secondary analysis of snake bite data in the Western Region of Ghana: 2006-2010.

BACKGROUND: A snake bite is an injury caused by a bite from a snake, often resulting in puncture wounds, amputations and sometimes envenomation. Envenoming resulting from snake bite is a particularly important public health problem in rural areas of tropical and sub-tropical countries in Africa. This paper reports the incidence of snake bites and its associated mortality in the Western Region of Ghana. METHOD: The study was a descriptive cross-sectional review of 2006 - 2010 snake bite secondary data generated by the Western Regional Health Information Office in Ghana. Data was extracted from the District Health Information Management System (DHIMS) database. Data was managed and analyzed using SPSS Version 16.0. Univariate analyses were expressed as percentages and graphs. RESULTS: The year 2009 recorded the highest incidence of Snake bites in the Western Region with Juabeso district recording the highest incidence of snake bites over the study period. Over the period about 55% of the incidence was between 50 - 100 per 100,000 population. The total number of snake bites recorded in the region for the period was 7,275, of which 52% (3,776) were males. About 60% of the patients were of the age group 15-49 years. A total of 12 reported snake bite deaths were recorded, of which 67% were men. This study recommends to the Districts Health Directorates in the Western Region to regularly organize community education on snake bite and the use of protective clothing by the farmers. FUNDING: None declared.

Environmental Isolation of Circulating Vaccine-Derived Poliovirus After Interruption of Wild Poliovirus Transmission - Nigeria, 2016.

In September 2015, more than 1 year after reporting its last wild poliovirus (WPV) case in July 2014 (1), Nigeria was removed from the list of countries with endemic poliovirus transmission,* leaving Afghanistan and Pakistan as the only remaining countries with endemic WPV. However, on April 29, 2016, a laboratory-confirmed, circulating vaccine-derived poliovirus type 2 (cVDPV2) isolate was reported from an environmental sample collected in March from a sewage effluent site in Maiduguri Municipal Council, Borno State, a security-compromised area in northeastern Nigeria. VDPVs are genetic variants of the vaccine viruses with the potential to cause paralysis and can circulate in areas with low population immunity. The Nigeria National Polio Emergency Operations Center initiated emergency response activities, including administration of at least 2 doses of oral poliovirus vaccine (OPV) to all children aged <5 years through mass campaigns; retroactive searches for missed cases of acute flaccid paralysis (AFP), and enhanced environmental surveillance. Approximately 1 million children were vaccinated in the first OPV round. Thirteen previously unreported AFP cases were identified. Enhanced environmental surveillance has not resulted in detection of additional VDPV isolates. The detection of persistent circulation of VDPV2 in Borno State highlights the low population immunity, surveillance limitations, and risk for international spread of cVDPVs associated with insurgency-related insecurity. Increasing vaccination coverage with additional targeted supplemental immunization activities and reestablishment of effective routine immunization activities in newly secured and difficult-to-reach areas in Borno is urgently needed.

Clinical profile and containment of the Ebola virus disease outbreak in two large West African cities, Nigeria, July-September 2014.

INTRODUCTION: The Ebola virus disease (EVD) outbreak in Nigeria began when an infected diplomat from Liberia arrived in Lagos, the most populous city in Africa, with subsequent transmission to another large city. METHODS: First-, second-, and third-generation contacts were traced, monitored, and classified. Symptomatic contacts were managed at Ebola treatment centers as suspected, probable, and confirmed EVD cases using standard operating procedures adapted from the World Health Organization EVD guidelines. Reverse transcription PCR tests confirmed EVD. Socio-demographic, clinical, hospitalization, and outcome data of the July-September 2014 Nigeria EVD cohort were analyzed. RESULTS: The median age of the 20 EVD cases was 33 years (interquartile range 26-62 years). More females (55%), health workers (65%), and persons <40 years old (60%) were infected than males, non-health workers, and persons aged ≥40 years. No EVD case management worker contracted the disease. Presenting symptoms were fever (85%), fatigue (70%), and diarrhea (65%). Clinical syndromes were gastroenteritis (45%), hemorrhage (30%), and encephalopathy (15%). The case-fatality rate was 40% and there was one mental health complication. The average duration from symptom onset to presentation was 3±2 days among survivors and 5±2 days for non-survivors. The mean duration from symptom onset to discharge was 15±5 days for survivors and 11±2 days for non-survivors. Mortality was higher in the older age group, males, and those presenting late. CONCLUSION: The EVD outbreak in Nigeria was characterized by the severe febrile gastroenteritis syndrome typical of the West African outbreak, better outcomes, rapid containment, and no infection among EVD care-providers. Early case detection, an effective incident management system, and prompt case management with on-site mobilization and training of local professionals were key to the outcome.

Epidemiological profile of the Ebola virus disease outbreak in Nigeria, July-September 2014.

INTRODUCTION: In July 2014, Nigeria experienced an outbreak of Ebola virus disease following the introduction of the disease by an ill Liberian Traveler. The Government of Nigeria with the support of Technical and Development Partners responded quickly and effectively to contain the outbreak. The epidemiological profile of the outbreak that majorly affected two States in the country in terms of person, place and time characteristics of the cases identified is hereby described. METHODS: Using field investigation technique, all confirmed and probable cases were identified, line-listed and analysed using Microsoft Excel 2007 by persons, time and place. RESULTS: A total of 20 confirmed and probable cases; 16 in Lagos (including the index case from Liberia) and 4 in Port Harcourt were identified. The mean age was 39.5 ± 12.4 years with over 40% within the age group 30-39 years. The most frequent exposure type was direct physical contact in 70% of all cases and 73% among health care workers. The total case-fatality was 40%; higher among healthcare workers (46%) compared with non-healthcare workers (22%). The epidemic curve initially shows a typical common source outbreak, followed by a propagated pattern. CONCLUSION: Investigation revealed the size and spread of the outbreak and provided information on the characteristics of persons, time and place. Enhanced surveillance measures, including contact tracing and follow- up proved very useful in early case detection and containment of the outbreak.

An evaluation of psychological distress and social support of survivors and contacts of Ebola virus disease infection and their relatives in Lagos, Nigeria: a cross sectional study--2014.

BACKGROUND: By September 2014, an outbreak of Ebola Viral Disease (EVD) in West African countries of Guinea, Liberia, Sierra Leone, Senegal and Nigeria, had recorded over 4500 and 2200 probable or confirmed cases and deaths respectively. EVD, an emerging infectious disease, can create fear and panic among patients, contacts and relatives, which could be a risk factor for psychological distress. Psychological distress among this subgroup could have public health implication for control of EVD, because of potential effects on patient management and contact tracing. We determined the Prevalence, pattern and factors associated with psychological distress among survivors and contacts of EVD and their relatives. METHODS: In a descriptive cross sectional study, we used General Health Questionnaire to assess psychological distress and Oslo Social Support Scale to assess social support among 117 participants who survived EVD, listed as EVD contacts or their relatives at Ebola Emergency Operation Center in Lagos, Nigeria. Factors associated with psychological distress were determined using chi square/odds ratio and adjusted odds ratio. RESULTS: The mean age and standard deviation of participants was 34 +/ - 9.6 years. Of 117 participants, 78 (66.7%) were females, 77 (65.8%) had a tertiary education and 45 (38.5%) were health workers. Most frequently occurring psychological distress were inability to concentrate (37.6%) and loss of sleep over worry (33.3%). Losing a relation to EVD outbreak (OR = 6.0, 95% CI, 1.2-32.9) was significantly associated with feeling unhappy or depressed while being a health worker was protective (OR = 0.4, 95% CI, 0.2-0.9). Adjusted Odds Ratio (AOR) showed losing a relation (AOR = 5.7, 95% CI, 1.2-28.0) was a predictor of "feeling unhappy or depressed", loss of a relation (AOR = 10.1, 95% CI, 1.7-60.7) was a predictor of inability to concentrate. CONCLUSIONS: Survivors and contacts of EVD and their relations develop psychological distress. Development of psychological distress could be predicted by loss of family member. It is recommended that psychiatrists and other mental health specialists be part of case management teams. The clinical teams managing EVD patients should be trained on recognition of common psychological distress among patients. A mental health specialist should review contacts being monitored for EVD for psychological distress or disorders.

Polio eradication in Nigeria and the role of the National Stop Transmission of Polio program, 2012-2013.

To strengthen the Nigeria polio eradication program at the operational level, the National Stop Transmission of Polio (N-STOP) program was established in July 2012 as a collaborative effort of the National Primary Health Care Development Agency, the Nigerian Field Epidemiology and Laboratory Training Program, and the US Centers for Disease Control and Prevention. Since its inception, N-STOP has recruited and trained 125 full-time staff, 50 residents in training, and 50 ad hoc officers. N-STOP officers, working at national, state, and district levels, have conducted enumeration outreaches in 46,437 nomadic and hard-to-reach settlements in 253 districts of 19 states, supported supplementary immunization activities in 236 districts, and strengthened routine immunization in 100 districts. Officers have also conducted surveillance assessments, outbreak response, and applied research as needs evolved. The N-STOP program has successfully enhanced Global Polio Eradication Initiative partnerships and outreach in Nigeria, providing an accessible, flexible, and culturally competent technical workforce at the front lines of public health. N-STOP will continue to respond to polio eradication program needs and remain a model for other healthcare initiatives in Nigeria and elsewhere.

Outreach to underserved communities in northern Nigeria, 2012-2013.

BACKGROUND: Persistent wild poliovirus transmission in Nigeria constitutes a major obstacle to global polio eradication. In August 2012, the Nigerian national polio program implemented a strategy to conduct outreach to underserved communities within the context of the country's polio emergency action plans. METHODS: A standard operating procedure (SOP) for outreach to underserved communities was developed and included in the national guidelines for management of supplemental immunization activities (SIAs). The SOP included the following key elements: (1) community engagement meetings, (2) training of field teams, (3) field work, and (4) acute flaccid paralysis surveillance. RESULTS: Of the 46,437 settlements visited and enumerated during the outreach activities, 8607 (19%) reported that vaccination teams did not visit their settlements during prior SIAs, and 5112 (11.0%) reported never having been visited by polio vaccination teams. Fifty-two percent of enumerated settlements (23,944) were not found in the existing microplan used for the immediate past SIAs. CONCLUSIONS: During a year of outreach to >45,000 scattered, nomadic, and border settlements, approximately 1 in 5 identified were missed in the immediately preceding SIAs. These missed settlements housed a large number of previously unvaccinated children and potentially served as reservoirs for persistent wild poliovirus transmission in Nigeria.

An assessment of the reasons for oral poliovirus vaccine refusals in northern Nigeria.

BACKGROUND: Accumulation of susceptible children whose caregivers refuse to accept oral poliovirus vaccine (OPV) contributes to the spread of poliovirus in Nigeria. METHODS: During and immediately following the OPV campaign in October 2012, polio eradication partners conducted a study among households in which the vaccine was refused, using semistructured questionnaires. The selected study districts had a history of persistent OPV refusals in previous campaigns. RESULTS: Polio risk perception was low among study participants. The majority (59%) of participants believed that vaccination was either not necessary or would not be helpful, and 30% thought it might be harmful. Religious beliefs were an important driver in the way people understood disease. Fifty-two percent of 48 respondents reported that illnesses were due to God's will and/or destiny and that only God could protect them against illnesses. Only a minority (14%) of respondents indicated that polio was a significant problem in their community. CONCLUSIONS: Caregivers refuse OPV largely because of poor polio risk perception and religious beliefs. Communication strategies should, therefore, aim to increase awareness of polio as a real health threat and educate communities about the safety of the vaccine. In addition, polio eradication partners should collaborate with other agencies and ministries to improve total primary healthcare packages to address identified unmet health and social needs.

An evaluation of community perspectives and contributing factors to missed children during an oral polio vaccination campaign--Katsina State, Nigeria.

BACKGROUND: Unvaccinated children contribute to accumulation of susceptible persons and the continued transmission of wild poliovirus in Nigeria. In September 2012, the Expert Review Committee (ERC) on Polio Eradication and Routine Immunization in Nigeria recommended that social research be conducted to better understand why children are missed during supplementary immunization activities (SIAs), also known as "immunization plus days (IPDs)" in Nigeria. METHODS: Immediately following the SIA in October 2012, polio eradication partners and the government of Nigeria conducted a study to assess why children are missed. We used semistructured questionnaires and focus group discussions in 1 rural and 1 urban local government area (LGA) of Katsina State. RESULTS: Participants reported that 61% of the children were not vaccinated because of poor vaccination team performance: either the teams did not visit the homes (25%) or the children were reported absent and not revisited (36%). This lack of access to vaccine was more frequently reported by respondents from scattered/nomadic communities (85%). In 1 out of 4 respondents (25%), refusal was the main reason their child was not vaccinated. The majority of respondents reported they would have consented to their children being vaccinated if the vaccine had been offered. CONCLUSIONS: Poor vaccination team performance is a major contributor to missed children during IPD campaigns. Addressing such operational deficiencies will help close the polio immunity gap and eradicate polio from Nigeria.