A United States-backed study in West Africa on the effects of the hepatitis B vaccine is facing scrutiny from the World Health Organization and UNICEF, researchers involved in the study tell NOTUS.
Officials from the two international public health groups met with members of the Bandim Health Project earlier this week to discuss their recent announcement of a five-year, randomized controlled trial in Guinea-Bissau, in which some infants would receive the hepatitis B vaccine at birth and others at six weeks, according to Peter Aaby, the Danish researcher who heads the group.
Aaby told NOTUS that the meeting was called in response to news coverage criticizing the study, including an article in The Guardian in which vaccine experts called the study “highly unethical.”
The experts cited in that piece, which includes Paul Offit, the co-inventor of the rotavirus vaccine, said “a lot of things about something they know nothing about,” Aaby said.
In response, Offit told NOTUS that he would welcome a chance to review the specifics of how the group’s hepatitis B study would be carried out, but added that he could not imagine a form the study could take that he would view as ethical.
“The only thing that would alleviate my concern is if they took that $1.6 million and vaccinated as many kids at birth as the WHO recommends,” Offit said, referring to the funding the Bandim group’s study received from the Centers for Disease Control and Prevention.
The Bandim Project’s study protocol is in the process of being translated from Portuguese to English and will be available on the group’s website when complete, Aaby said.
Aaby said the meeting between the WHO, UNICEF and Bandim was “very successful” but didn’t elaborate on what was discussed. Another Bandim researcher, Isaquel de Silva, told NOTUS that the Bandim group was in conversations with international stakeholders, including the WHO and UNICEF, to “explain our idea and what we plan to do.”
The WHO and UNICEF did not immediately respond to requests for comment. The CDC did not immediately respond to a request for comment.
The current status of the Guinea-Bissau hepatitis B study is unclear. While the Bandim Health Project website said earlier this month that the project would begin in January 2026, the website was recently updated to remove that deadline and now says “preparations are ongoing.”
De Silva told NOTUS that they have not yet started the study and “didn’t have an idea yet when we will start.” He said that the Guinea-Bissau Ministry of Health had also expressed concerns over the research. The government of Guinea-Bissau did not immediately respond to requests for comment.
Aaby said he is confident the study will proceed and that the research group is currently waiting to receive vaccines and other materials.
“Everything takes time,” he said.
The December announcement of the study and the news that the United States was backing it were immediately marred by controversy. At least one scientist affiliated with the Bandim Health Project, Christine Stabell Benn, who is married to Aaby, has ties to the anti-vaccine movement in the United States.
News of the CDC’s grant came only weeks after Health Secretary Robert F. Kennedy Jr.'s hand-picked panel of vaccine reviewers, many of whom have previously expressed skepticism about vaccines, changed long-held recommendations for the hepatitis B vaccine for infants in the U.S.
Benn recently served as an expert witness to that panel, the CDC Advisory Committee on Immunization Practices. She did not respond to a request for comment.
Bandim Health Project states on its website that the study was designed to take advantage of a “unique a window of opportunity”: the Guinea-Bissau Ministry of Health currently recommends that infants receive the Hepatitis B vaccine at six weeks, but was planning to move to recommending infants receive the vaccine at birth beginning in 2027, as recommended by the WHO.
But Aaby told NOTUS that the Guinea-Bissau government, recently thrown into turmoil by a military coup, has pushed the birth dose rollout back to 2028.
Aaby said he did not know whether the change was in part due to the Bandim group’s proposed study, calling it a “complicated situation” with the government turnover. He said that the new date gave them a “bit more time” to conduct the study.
He also told NOTUS that he was troubled by the scrutiny on the hepatitis B study in Guinea-Bissau. The study was simply “a research protocol to answer this knowledge gap” on the wider effects of vaccines, Aaby said.
“I’m not doing political research,” he added. “I’m doing research in terms of, how do vaccines actually work?”
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