A controversial U.S.-funded study in Guinea-Bissau examining hepatitis B vaccines among newborns has been cancelled, according to Yap Boum, a senior official at the Africa Centres for Disease Control and Prevention (CDC). Boum announced the cancellation at a press conference Thursday morning, citing ethical concerns that arose from the study's design.

The $1.6 million project, 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 widespread criticism for its approach of withholding proven hepatitis B vaccines in a country with a high prevalence of the disease. Critics argued that withholding a life-saving vaccine for research purposes was unethical, especially given the established efficacy of hepatitis B vaccines in preventing infection and subsequent liver damage, cirrhosis, and liver cancer.

Hepatitis B is a viral infection that attacks the liver and can cause both acute and chronic disease. The virus is most commonly spread from mother to child during birth and delivery, as well as through contact with infected blood or other body fluids. Vaccination is a highly effective method of preventing hepatitis B infection, particularly when administered shortly after birth. The World Health Organization (WHO) recommends that all infants receive their first dose of the hepatitis B vaccine as soon as possible after birth, preferably within 24 hours, followed by two or three doses to complete the primary series.

“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 [cancelling the study],” Boum told journalists. The specific details of the study's design that led to the ethical concerns were not immediately clear, but the decision to halt the research reflects a commitment to ethical research practices and the well-being of the population in Guinea-Bissau.

The cancellation raises questions about the future of hepatitis B prevention efforts in Guinea-Bissau and the role of international research collaborations. It also highlights the importance of rigorous ethical review processes for all research involving human subjects, particularly in vulnerable populations. Further details regarding the study's objectives, methodology, and the specific ethical concerns that prompted its cancellation are expected to be released in the coming days.