The Tropis Polio Immunization Project (TroPIP) aimed to evaluate the impact of intradermal (ID) polio vaccine administration using the Tropis® Needle-free Injection System (NFIS) in Nigeria. The project sought to measure vaccine coverage and assess the cost-effectiveness of fractional inactivated poliovirus vaccine (fIPV) delivery through Tropis compared to traditional intramuscular (IM) delivery using needles.
In addition, the study evaluated the programmatic feasibility, sustainability, and potential for scale-up of the Tropis device within Nigeria’s Expanded Program on Immunization (EPI). The project was implemented from 2023 to 2024 in Kano and Oyo states, chosen based on specific criteria, including disease burden and logistical considerations.
A consortium of stakeholders including NPHCDA, PharmaJet, PATH, JHPIEGO, and Sydani worked collaboratively to assess this novel technology’s impact in routine immunization programs. The project involved three LGAs in Kano and four in Oyo, covering a total of 52 health facilities split between 22 intervention sites (where Tropis was introduced) and 30 control sites (standard IM injections used).
Action (Assessments/MEL/Data Management):
To evaluate the acceptability, feasibility, scalability, and sustainability of fIPV Tropis delivery within the immunization landscape (Aim 3), Sydani designed data collection tools and strategies to gather both qualitative and quantitative data. The data collection process involved Key Informant Interviews (KIIs) with key state and local health officials, including routine immunization officers, cold chain officers, and healthcare workers (HCWs).
Additionally, Focus Group Discussions (FGDs) were conducted with caregivers, and household and provider surveys were carried out to capture broader perspectives on the use of the Tropis device.
Data were collected from health facilities in both intervention and control sites to assess the comparative performance of Tropis. Insights were drawn from healthcare workers’ feedback on their experience with the device, as well as caregivers’ perceptions of its use during immunization sessions. This comprehensive approach helped provide a clearer understanding of how well Tropis could be integrated into Nigeria’s routine immunization system.
Result
The findings revealed a strong positive response to the Tropis device among both healthcare workers and caregivers. Healthcare workers noted that the Tropis system was easy to operate and presented a safer alternative to traditional needle-based injections.
They reported that the device contributed to a smoother immunization process, with children experiencing less discomfort, fewer adverse reactions, and overall reduced vaccine wastage compared to standard injections. This led to higher acceptance rates among caregivers, many of whom expressed satisfaction with the needle-free system and indicated that they were more likely to return for future vaccinations if Tropis was used.
Action (Capacity Building):
As part of the Tropis Polio Immunization Project (TroPIP), a key focus was on building the capacity of healthcare workers (HCWs) in Kano and Oyo states to successfully use the Tropis® Needle-free Injection System (NFIS) for administering the fractional inactivated poliovirus vaccine (fIPV).
Effective use of this device was critical for ensuring the smooth implementation of the study and achieving accurate, efficient vaccine delivery within the routine immunization system.
To equip HCWs with the necessary skills and knowledge, Sydani organized a two-day intensive training for healthcare workers in both Kano and Oyo states. A total of 33 HCWs per state participated in the training sessions, where they were trained on how to operate the Tropis device, handle fractional doses of IPV, manage potential challenges, and ensure proper documentation and reporting.
The training covered both theoretical and hands-on practice components, ensuring that HCWs fully understood the operational mechanics of the needle-free device. This included instructions on device safety, administering intradermal injections, and addressing any caregiver concerns or queries about the new technology. Throughout the training, participants were given ample opportunity to practice using the Tropis device to ensure proficiency.
Result:
Following the training, healthcare workers demonstrated full competence in the use of the Tropis device, ensuring that the study was conducted without any technical issues or disruptions. Feedback from both HCWs indicated that the training was successful, with HCWs quickly adapting to the new technology and integrating it into their routine immunization activities. Their confidence and skill in using the Tropis device contributed significantly to the smooth execution of the project, which resulted in over 70,000 children being vaccinated across Kano and Oyo states.
The capacity-building efforts ensured that HCWs were well-prepared to deliver fIPV using the Tropis system, setting a strong foundation for the potential scale-up of this innovative immunization approach across Nigeria’s routine immunization program.
The absence of crying or swelling among children after receiving the Tropis-administered vaccine was particularly appreciated by caregivers, contributing to a positive overall experience. Healthcare workers also noted the potential for Tropis to improve immunization coverage, as the device made the vaccination process more appealing to both caregivers and children, reducing
The project successfully demonstrated the acceptability, feasibility, and potential scalability of using the Tropis device for fIPV delivery. With 70,000 children vaccinated in Kano and Oyo states and no refusals from caregivers, the project exceeded expectations. The overwhelmingly positive response from both HCWs and caregivers, combined with significant reductions in vaccine wastage, underscored the potential for Tropis to transform routine immunization delivery. However, the sustainability of this technology would depend on strategic partnerships and funding to ensure that it can be implemented at scale across Nigeria.
