Adverse event following vaccine surveillance in Kaduna State, Northwestern Nigeria (January 2018 -June 2019): analysis of health facility´s records.

INTRODUCTION: Adverse Events Following Immunization (AEFI) are one of the main reasons for inadequate immunization coverage in Kaduna State, and AEFI underreporting serves as a barrier to achieving goals of global pharmaco-vigilance for vaccine. The purpose of this study is to estimate the completeness of variables in the AEFI line-listing forms, calculate AEFI reporting rates by Local Government Areas & vaccine type and profile the reported cases according to their reactions. METHODS: we conducted a descriptive, cross-sectional, retrospective study of primary surveillance records. We calculated AEFI reporting rates in the State and Local Government areas and AEFI Vaccine reaction rates to the various antigens. We used Binary logistic regression to determine the association between gender and vaccine reactions. RESULTS: seven thousand eight hundred and twenty-four (7,824) AEFI cases were reported. The completeness of variables on the filled AEFI line-list varied from 21% to 100%. The State had a high AEFI reporting rate of 9.09 per 10,000 administered doses. Fever (<38oC) was the main AEFI reaction. Severe AEFI cases accounted for only 0.89% of the total reported cases. Pentavalent vaccine was the suspect antigen responsible for the highest number of AEFI cases, with a vaccine reaction rate of 44.77 per 10,000 doses. The Zaria Local Government area had the highest AEFI reporting rate, while the Sanga Local Government area had the lowest AEFI reporting rate in the State. The difference between genders in the number of reported AEFI cases was not statistically significant (p>0.05). There were 35% higher odds of occurrence of bleeding among males than among females (aOR: 1.354; P-value: p=.012; 95% CI: 1.070-1.715; Nagelkerke-R2-: 0.003). The other reactions were not significantly related to gender. CONCLUSION: our study shows a higher occurrence of severe AEFI in subjects undergoing pentavalent vaccine. Thiscaused the highest incidence of AEFI. There was no significant association between gender and AEFI reactions.

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.

Assessment of unmet needs to address noncompliant households during polio supplemental immunization activities in Kaduna state, 2014-2016.

BACKGROUND: Despite concerted global efforts being made to eradicate poliomyelitis, the wild poliovirus still circulates in three countries, including Nigeria. In addition, Nigeria experiences occasional outbreaks of the circulating vaccine-derived poliovirus type 2 (cVDPV2). Vaccine rejection by caregivers persists in some parts of northern Nigeria, which compromises the quality of supplemental immunization activities (SIAs). In 2013, the Expert Review Committee (ERC) on polio recommended innovative interventions in all high-risk northern states to improve the quality of SIA rounds through innovative interventions. The study assessed the impact of using unmet needs data to develop effective strategies to address noncompliant households in 13 high-risk Local government areas (LGAs) in Kaduna state, Nigeria. METHODS: A retrospective study was conducted in noncompliant communities using unmet needs data collated from 2014 to 2016. Household-based noncompliance data collated from tally sheets between 2013 and 2016 was also analyzed to assess the impact of unmet needs data in addressing noncompliance households in high-risk communities in Kaduna state. A structured interview was used to interview caregivers by the application of an unmet needs questionnaire, a quantitative study that assesses caregiver perception on immunization and other unmet needs which, if the gaps were addressed, would allow them to accept immunization services. Interventions include siting of temporary health camps in noncompliant communities to provide free medical consultations, treatment of minor ailments, provision of free antimalaria drugs and other essential drugs, and also referral of serious cases; intervention of religious and traditional leaders, youth against polio intervention, and the use of attractive bonuses (sweets, balloons, milk) during SIAs were all innovations applied to reduce noncompliance in households in affected communities as the need for eradication of polio was declared as a state of emergency. Outcomes from the analyses of unmet needs data were used to direct specific interventions to certain areas where they will be more effective in reducing the number of noncompliant households recorded on the tally sheet in each SIA round. Hence, seven immunization parameters were assessed from the unmet needs data. RESULTS: Overall, 54% of the noncompliant caregivers interviewed were ready to support immunization services in their communities. The majority of caregivers were also willing to vaccinate their children publicly following unmet needs interventions that were conducted in noncompliant communities. The trend of noncompliant households decreased by 79% from 16,331 in September 2013 to 3394 in May 2016. CONCLUSIONS: Unmet needs interventions were effective in reducing the number of noncompliant households recorded during SIA rounds in Kaduna State. Hence, unmet needs intervention could be adapted at all levels to address challenges faced in other primary healthcare programs in Nigeria.

Acute flaccid paralysis (AFP) surveillance intensification for polio certification in Kaduna state, Nigeria: lessons learnt, 2015-2016.

BACKGROUND: Nigeria has made remarkable progress in its current efforts to interrupt wild poliovirus transmission despite the re-emergence of wild poliovirus in 2016. The gains made in Nigeria have been achieved through concerted efforts by governments at all levels, traditional leaders, health workers, caregivers, and development partners. The efforts have involved an elaborate plan, coordination, and effective implementation of routine immunization services, supplemental immunization activities, and acute flaccid paralysis (AFP) surveillance. METHODS: We conducted the following activities to strengthen AFP surveillance in Kaduna state: a monetary reward for all AFP cases reported by health workers or community informants and verified as "true" AFP by a World Health Organization (WHO) cluster coordinator; training and sensitization of surveillance officers, clinicians, and community informants; recruitment of more personnel and expansion of the surveillance network; and the involvement of special populations (nomadic, hard-to-reach, and border communities) and caregivers in stool sample collection. The paired t test was used to evaluate the impact of the different initiatives implemented in Kaduna state to intensify AFP surveillance in 2016. RESULTS: There was increased annualized non-polio AFP rate (ANPAFPR) in 21 out of 23 Local Government Areas (LGAs) of Kaduna state 6 months after implementation of different initiatives to intensify AFP surveillance. The AFP reported by the special population increased in 15 out of 23 LGAs. Statistical analyses of mean scores of ANPAFPR before and after the interventions using the paired t test revealed a significant difference in mean scores: mean = 19.7 (standard deviation (SD) = 16.1) per 100,000 < 15 years old in July-December 2015, compared with 38.0 (SD = 21.6) per 100,000 < 15 years old in January-June 2016 (p < 0.05). Likewise, analysis of silent wards using the paired t test showed a significant difference in mean scores: mean = 4.0 (SD = 2.1) in July-December 2015 compared with 2.4 (SD = 1.8) in January-June 2016 (p < 0.05). CONCLUSION: The different initiatives implemented in 23 LGAs of Kaduna state to intensify AFP surveillance may be responsible for the significant improvement in the AFP surveillance performance indicators in 2016.

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.