Improving the timeliness and completeness of childhood vaccination through color-coded bracelets: a pilot study among Fulani tribe populations in Nigeria

Background

Childhood immunization remains one of the most cost-effective public health interventions. Globally, millions of children are not being reached with safe and effective vaccines and Nigeria has the highest number of unprotected children.

Objective

The effects of locally adapted interventions on vaccination timeliness and completeness were studied amongst Fulani populations across 6 health facilities in 2 districts of Bauchi State, Nigeria.

Methods

The intervention group consisted of newborns who received 5-color-coded bracelets representing different immunization contacts, while the control group had no bracelets. Vaccination rates across contacts were followed for 11 months. In addition, mothers of children in the intervention group were voluntarily recruited as peer-to-peer mobilizers (PPM).

Results

In this study, 435 children were studied. Vaccination completeness was higher in the intervention group compared to the control group at all contacts during follow-up. The difference was most noticeable at the fifth contact, with 158/256 (62%) children in the intervention group completing, compared to 73/179 (41%) in the control group (P<0.0001). Vaccination timeliness was better in the intervention group compared to the control one, which reached statistical significance at the second and third vaccination contacts (P<0.05). 68% of women volunteered as PPM and recruited 82 additional children for vaccination.

Conclusion

This study demonstrated the feasibility of a composite intervention (bracelets and PPM) to increase the completeness and timeliness of childhood immunization and provided preliminary evidence for its efficacy among Fulani populations in Nigeria. Findings from this pilot study should be confirmed through a larger cluster randomized controlled trial.

Randomized Controlled Clinical Trial of bivalent Oral Poliovirus Vaccine and Inactivated Poliovirus Vaccine in Nigerian Children

BACKGROUND

We conducted a trial in Nigeria to assess the immunogenicity of the new bOPV + IPV immunization schedule and gains in type 2 immunity with addition of second dose of IPV. The trial was conducted in August 2016-March 2017 period, well past the tOPV-bOPV switch in April 2016.

METHODS

This was an open-label, two-arm, non-inferiority, multi-center, randomized controlled trial. We enrolled 572 infants of age ≤14 days and randomized them into two arms. Arm A received bOPV at birth, 6 and 10 weeks, bOPV+IPV at week 14 and IPV at week 18. Arm B received IPV each at 6, 10, 14 weeks and bOPV at 18 weeks of age.

RESULTS

Seroconversion rates for poliovirus types 1 and 3, respectively, were 98.9% (95%CI:96.7-99.8) and 98.1% (95%CI:88.2-94.8) in Arm A, and 89.6% (95%CI:85.4-93.0) and 98.5% (95%CI:96.3-99.6) in Arm B. Type 2 seroconversion with one dose IPV in Arm A was 72.0% (95%CI:66.2-77.3), which increased significantly with addition of second dose to 95.9% (95%CI:92.8-97.9).

CONCLUSION

This first trial on the new EPI schedule in a sub-Saharan African country demonstrated excellent immunogenicity against poliovirus types 1 and 3, and substantial/enhanced immunogenicity against poliovirus type 2 after 1 to 2 doses of IPV respectively.

Combining cluster surveys to estimate vaccination coverage: Experiences from Nigeria's multiple indicator cluster survey / national immunization coverage survey (MICS/NICS), 2016-17

•

Nigeria's immunization stakeholders cooperated on the 2016–17 MICS/NICS survey.

•

Extra survey clusters were added in 20 states to improve outcome precision.

•

Data from MICS & supplementary clusters were pooled after passing a statistical test.

•

Combined results were used to guide policy, but not as precise as originally hoped.

•

We explore organizational aspects of cooperation & technical aspects of pooled data.

In 2015 immunization stakeholders in Nigeria were proceeding with plans that would have fielded two nationally representative surveys to estimate vaccination coverage at the same time. Rather than duplicate efforts and generate either conflicting or redundant results, the stakeholders collaborated to conduct a combined Multiple Indicator Cluster Survey (MICS) / National Immunization Coverage Survey (NICS) with MICS focusing on core sampling clusters and NICS adding supplementary clusters in 20 states, to improve precision of outcomes there. This paper describes the organizational and technical aspects of that collaboration, including details on design of the sample supplement and analysis of the pooled dataset. While complicated, the collaboration was successful; it yielded a unified set of relevant coverage estimates and fostered some novel sub-national results dissemination work.

Vaccine wastage in Nigeria: An assessment of wastage rates and related vaccinator knowledge, attitudes and practices

INTRODUCTION

The introduction of new vaccines highlights concerns about high vaccine wastage, knowledge of wastage policies and quality of stock management. However, an emphasis on minimizing wastage rates may cause confusion when recommendations are also being made to reduce missed opportunities to routinely vaccinate children. This concern is most relevant for lyophilized vaccines without preservatives [e.g. measles-containing vaccine (MCV)], which can be used for a limited time once reconstituted.

METHODS

We sampled 54 health facilities within 11 local government areas (LGAs) in Nigeria and surveyed health sector personnel regarding routine vaccine usage and wastage-related knowledge and practices, conducted facility exit interviews with caregivers of children about missed opportunities for routine vaccination, and abstracted vaccine stock records and vaccination session data over a 6-month period to calculate wastage rates and vaccine vial usage patterns.

RESULTS

Nearly half of facilities had incomplete vaccine stock data for calculating wastage rates. Among facilities with sufficient data, mean monthly facility-level wastage rates were between 18 and 35% across all reviewed vaccines, with little difference between lyophilized and liquid vaccines. Most (98%) vaccinators believed high wastage led to recent vaccine stockouts, yet only 55% were familiar with the multi-dose vial policy for minimizing wastage. On average, vaccinators reported that a minimum of six children must be present prior to opening a 10-dose MCV vial. Third dose of diphtheria-tetanus-pertussis vaccine (DTP3) was administered in 84% of sessions and MCV in 63%; however, the number of MCV and DTP3 doses administered were similar indicating the number of children vaccinated with DTP3 and MCV were similar despite less frequent MCV vaccination opportunities. Among caregivers, 30% reported being turned away for vaccination at least once; 53% of these children had not yet received the missed dose.

DISCUSSION

Our findings show inadequate implementation of vaccine management guidelines, missed opportunities to vaccinate, and lyophilized vaccine wastage rates below expected rates. Missed opportunities for vaccination may occur due to how the health system's contradicting policies may force health workers to prioritize reduced wastage rates over vaccine administration, particularly for multi-dose vials.

Poliovirus seroprevalence before and after interruption of poliovirus transmission in Kano State, Nigeria

•

Polio seroprevalence surveys help measure progress towards polio eradication.

•

Nigeria program conducted multiple seroprevalence surveys in northern states.

•

This article covers seroprevalence survey in Kano Nigeria in 2013 and 2014.

•

Data represents levels before and after the interruption of poliovirus transmission.

•

Significant improvement in seroprevalence in 2014 over 2013, but gaps continue.

•

Good participation even by vaccine refusers in this health facility based project.

Introduction

In September 2015, Nigeria was removed from the list of polio-endemic countries after more than 12 months had passed since the detection of last wild poliovirus case in the country on 24 July 2014. We are presenting here a report of two polio seroprevalence surveys conducted in September 2013 and October 2014, respectively, in the Kano state of northern Nigeria.

Methods

Health facility based seroprevalence surveys were undertaken at Murtala Mohammad Specialist Hospital, Kano. Parents or guardians of children aged 6–9 months, 36–47 months, 5–9 years and 10–14 years in 2013 and 6–9 months and 19–22 months (corresponding to 6–9 months range at the time of 2013 survey) in 2014 presenting to the outpatient department, were approached for participation, screened for eligibility and asked to provide informed consent. A questionnaire was administered and a blood sample collected for polio neutralization assay.

Results

Among subjects aged 6–9 months in the 2013 survey, seroprevalence was 58% (95% confidence interval [CI] 51–66%) to poliovirus type 1, 42% (95% CI 34–50%) to poliovirus type 2, and 52% (95% CI 44–60%) to poliovirus type 3. Among children 36–47 months and older, seroprevalence was 85% or higher for all three serotypes. In 2014, seroprevalence in 6–9 month infants was 72% (95% CI 65–79%) for type 1, 59% (95% CI 52–66%) for type 2, and 65% (95% CI 57–72%) for type 3 and in 19–22 months, 80% (95% CI 74–85%), 57% (49–63%) and 78% (71–83%) respectively. Seroprevalence was positively associated with history of increasing oral poliovirus vaccine doses.

Conclusions

There was significant improvement in seroprevalence in 2014 over the 2013 levels indicating a positive impact of recent programmatic interventions. However the continued low seroprevalence in 6–9 month age is a concern and calls for improved immunization efforts to sustain the polio-free Nigeria.