The $1.6 million study, funded under the purview of Robert F Kennedy Jr., a known vaccine skeptic and the secretary of the US Department of Health and Human Services (HHS), sparked outrage due to its methodology. Critics argued that withholding hepatitis B vaccines from newborns in a region with a high prevalence of the disease raised serious ethical questions.

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, where chronic infection rates are significantly higher than in other parts of the world. Vaccination is a safe and effective method of preventing hepatitis B infection, especially when administered shortly after birth.

The study's premise was to investigate alternative vaccination schedules, but the decision to withhold the standard vaccine protocol from a control group generated substantial opposition from public health experts and advocacy groups. They argued that any potential benefits from the study did not outweigh the risk of exposing newborns to preventable infection.

"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," Boum stated, emphasizing the importance of ethical considerations in research.

The cancellation of the study raises questions about the oversight and ethical review processes for international research projects, particularly those funded by entities with known biases against established medical interventions. It also highlights the ongoing debate surrounding vaccine hesitancy and its potential impact on public health initiatives. The Africa CDC is now expected to review its protocols for approving and monitoring research projects to ensure adherence to the highest ethical standards. The future of hepatitis B prevention efforts in Guinea-Bissau remains focused on ensuring widespread access to existing, proven vaccination strategies.