The $1.6 million study, funded under the purview of Robert F. Kennedy Jr., a known vaccine skeptic, and the U.S. Department of Health and Human Services (HHS), sparked outrage due to its methodology of withholding proven hepatitis B vaccines in a region with a high prevalence of the disease. Critics argued that withholding a life-saving vaccine for research purposes was unethical, particularly in a vulnerable population.

Hepatitis B is a viral infection that attacks the liver and can cause both acute and chronic disease. According to the World Health Organization (WHO), it is a major global health problem, particularly in Africa and Asia. The hepatitis B vaccine is highly effective in preventing infection, especially when administered shortly after birth. Without vaccination, infants born to infected mothers have a high risk of developing chronic hepatitis B, which can lead to liver cirrhosis and liver cancer.

“It’s of importance for Africa CDC to have evidence that can be translated in policy, but this has to be done within the norm. So we ar[e]…,” Boum stated, emphasizing the importance of ethical considerations in research.

The study's cancellation raises questions about the oversight and ethical review processes for international research projects funded by the U.S. government. It also highlights the ongoing debate surrounding vaccine hesitancy and the potential influence of individuals with anti-vaccine views on public health policy. The implications of this cancellation for future hepatitis B prevention efforts in Guinea-Bissau and similar high-burden regions remain to be seen. Further details regarding the specific ethical concerns and the study's design have not been publicly released.