Boum announced the cancellation at a press conference on Thursday morning, stating, "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 are glad..." The study, funded under the purview of the U.S. Department of Health and Human Services (HHS), drew criticism for raising ethical questions about withholding hepatitis B vaccines in a country with a high prevalence of the disease. Robert F. Kennedy Jr., a longtime vaccine skeptic, was also associated with the funding.

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. The standard of care is vaccination at birth, which is highly effective in preventing the disease. The ethical concerns arose from the study's design, which reportedly involved withholding the vaccine from some newborns to study the impact.

The Africa CDC emphasizes the importance of evidence-based policy-making but insists that research must adhere to ethical norms. The cancellation reflects a commitment to ensuring that public health interventions are conducted responsibly and with the well-being of the population as the top priority. The implications of this cancellation are still unfolding, but it underscores the critical need for ethical oversight in international health research, particularly in vulnerable populations. Further details regarding the study's design and the specific ethical concerns have not been fully disclosed.