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Published on: November 1, 2011
Vaccine trials in the developing world: operational lessons learnt from a phase IV poliomyelitis vaccine trial in
H Geldenhuys1, Z Waggie, M Jacks
1South African Tuberculosis Vaccine Initiative, Institute of Infectious Diseases and Molecular Medicine (IIDMM), University of Cape Town, South Africa. hennie.geldenhuys@uct.ac.za
Background:
Conducting vaccine trials in developing nations is necessary but operationally complex. We describe operational lessons learnt from a phase IV poliomyelitis vaccine trial in a semi-rural region of South Africa.
Methods:
We reviewed operational data collected over the duration of the trial with respect to staff recruitment and training, participant recruitment and retention, and cold chain maintenance. RESULTS-LESSONS LEARNT: The recruitment model we used that relied on the 24h physical presence of a team member in the birthing unit was expensive and challenging to manage. Forecasting of enrolment rates was complicated by incomplete baseline data and by the linear nature of forecasts that do not take into account changing variables. We found that analyzing key operational data to monitor progress of the trial enabled us to identify problem areas timeously, and to facilitate a collegial problem-solving process by the extended trial team. Pro-actively nurturing a working relationship with the public sector health care system and the community was critical to our success. Despite the wide geographical area and lack of fixed addresses, we maintained an excellent retention rate through community assistance and the use of descriptive residential information. Training needs of team members were ongoing and dynamic and we discovered that these needs that were best met by an in-house, targeted and systemized training programme. The use of vaccine refrigerators instead of standard frost-free refrigerators is cost-effective and necessary to maintain the cold-chain.
Conclusion:
Operational challenges of a vaccine trial in developing world populations include inexperienced staff, the close liaison required between researchers and public health care services, impoverished participants that require complex recruitment and retention strategies, and challenges of distance and access. These challenges can be overcome by innovative strategies that allow for the unique characteristics of the setting, trial population, and trial team.
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