Randomized control trail for reducing vaccine hesitancy in sub-saharan Africa

1. RANDOMIZED CONTROL TRIALS:
ROLE OF CLINICAL TRIALS IN THE
REDUCTION OF VACCINE
HESITANCY IN NIGERIA

2. Outline
• Introduction
• Understanding Vaccine Hesitancy
• The Importance of Vaccines in Public Health
• Overview of Randomized Controlled Trials
• RCTs Relevant to Vaccination
• Clinical Trials in Nigeria – Historical Context
• Role of RCTs in Reducing Vaccine Hesitancy
• Evidence from Recent Clinical Trials
• Case Study: MenAfriVac Trials
• Challenges in Using RCTs to Address Hesitancy
• Recommendations
• Conclusion

3. Introduction
• Vaccine hesitancy is a significant
public health challenge globally and in
Nigeria (Ibekwe et al., 2024)
• Randomized Controlled Trials (RCTs)
provide evidence-based strategies to
address public mistrust.
• This presentation explores how
clinical trials, especially RCTs,
contribute to vaccine acceptance and
uptake in Nigeria.

4. Understanding
Vaccine Hesitancy
• Defined by WHO as the delay in
acceptance or refusal of
vaccines despite availability.
• Influenced factors including:
• Misinformation
• cultural beliefs
• mistrust in health systems
• Complacency
• High prevalence in Northern
Nigeria due to historical,
religious, and socio-political
factors.

5. The Importance of Vaccines in Public
Health
• Impact of vaccines on
reducing infectious diseases.
• The role of vaccination in
controlling outbreaks
• Polio
• measles

6. Overview of Randomized Controlled Trials
• RCTs: gold standard for testing the
efficacy of medical intervention in clinical
research.
• Participants are randomly assigned to
intervention or control groups.
• Reduce bias and establish causal
relationships.

7. RCTs Relevant to Vaccination
• Individually Randomized Trials
• Cluster-Randomized Trials
• Stepped-Wedge Designs
• Used to evaluate vaccine effectiveness,
safety, and community perceptions.

8. Clinical Trials in Nigeria – Historical Context
• Nigeria has hosted major vaccine trials
(e.g., MenAfriVac, COVID-19 vaccine
trials).
• Past controversies (e.g., Pfizer 1996
Trovan trial) influenced public trust
(Lenzer, 2006)
• Rebuilding trust through transparency
and community engagement.

9. Role of RCTs in Reducing Vaccine Hesitancy
• Provide reliable data on vaccine safety
and effectiveness.
• RCTs in community settings foster
transparency and inclusion.
• Educate the public and healthcare
workers, increasing confidence.

10. Evidence from Recent Clinical Trials
• COVID-19 vaccine trials: involved
Nigerian participants. E.g., Oxford-
AstraZeneca (Eguavoen et al., 2023)
• Result: increased vaccine confidence
post-trials in some urban communities.
• Community-based education during RCTs
improved acceptance.

11. Case Study: MenAfriVac Trials
• Conducted in Nigeria and other West
African countries (Borrow et al., 2015).
• Demonstrated high efficacy and
community engagement strategies.
• Helped reduce meningitis A and
improved perception of vaccines.

12. Challenges in Using RCTs
to Address Hesitancy
• Ethical concerns in low-resource
settings.
• Mistrust due to historical
exploitation.
• Limited awareness of clinical
trial processes.
• Inadequate representation of
rural communities.

13. Recommendations
• Strengthen community
engagement in trial design and
implementation.
• Promote public education on the
role of RCTs in health improvement.
• Collaborate with local leaders to
dispel myths.
• Ensure equitable inclusion in
clinical trials.

14. Conclusion
• RCTs are vital tools in building public trust and
demonstrating vaccine safety and efficacy.
• In Nigeria, well-conducted clinical trials have helped dispel
myths and foster community acceptance, especially when
paired with effective engagement and education strategies.
• Despite historical challenges, the integration of transparent,
inclusive, and ethically grounded RCTs can play a key role in
reducing vaccine hesitancy.
• Going forward, policy makers, researchers, and community
leaders must collaborate to leverage RCTs as both scientific
and social instruments in strengthening immunization
programs.

15. References
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