Key facts
- The proposed trial was designed to involve 14,000 newborns, with half receiving a hepatitis B vaccine shortly after birth and the other half not.
- The CDC awarded the University of Southern Denmark $1.6 million in December 2025 for the study.
- WHO representative Walter Kazadi Mulombo said withholding a vaccine proven to protect newborns is unethical.
- Health Minister Quinhin Nantote said the suspension remained in force and had not been overturned by the Council of Ministers.
- Guinea-Bissau's Judicial Police seized a batch of hepatitis B vaccines from the Bandim Health Project on October 19.
- SDU dean Jakob Grauslund said the trial never started, no babies were enrolled and no vaccinations were administered.
A proposed trial of a hepatitis B vaccine on newborn babies in Guinea-Bissau has been cancelled after accusations that it was unethical and neocolonial, the BBC reported on November 5, 2026. The study was planned at the Bandim Health Project, a research centre that has operated in Guinea-Bissau since 1978, and was designed to involve 14,000 newborns, with half receiving a hepatitis B vaccine shortly after birth and the other half not being given the shot.
The Trump administration funded the proposed study, with the CDC awarding the University of Southern Denmark $1.6 million in December 2025. Bandim said the trial aimed to investigate whether the hepatitis B vaccine given at birth has broader health effects beyond preventing infection. Researchers argued that because Guinea-Bissau does not currently offer routine hepatitis B vaccinations at birth, despite WHO recommendations, they had a unique opportunity to study its effects before such vaccines were introduced in 2028.
Walter Kazadi Mulombo, the WHO representative in Guinea-Bissau, told the BBC the agency became concerned after receiving questions about the study and finding no publicly available protocol. He said the main ethical concern was that the trial would withhold an intervention already proven to protect newborns against hepatitis B. "The vaccine has been used for more than 30 years in more than 115 countries," he said. "A study that will withhold that intervention from other newborns is unethical." Nearly a fifth of the population of Guinea-Bissau are infected with hepatitis B, and those infected during infancy are particularly likely to develop chronic infections, which kill up to 25% of people, mostly through liver failure or liver cancer, according to data published in 2020.
Guinea-Bissau's government prohibited hepatitis B vaccine trials involving children in January and requested a team of experts from the Africa Centres for Disease Control and Prevention to help evaluate the study. Health Minister Quinhin Nantote said in October that the suspension remained in force and had not been overturned by the Council of Ministers after reports emerged claiming that the trial would be taking place after all. "We were surprised to learn from media reports that the study might proceed," Nantote said. "We are outraged because even I, as the minister responsible for this sector, was not informed." The dispute intensified after the University of Southern Denmark said a revised study protocol had received ethical approval "from the relevant authorities in Guinea-Bissau," which Nantote denied.