The World Health Organization (WHO) has criticized a US-funded hepatitis B vaccine trial in Guinea-Bissau, calling it “unethical” for proposing to delay life-saving vaccination for thousands of newborns.
The study, led by Danish researchers and funded by the US Health Department, aimed to give one group of babies the hepatitis B vaccine at birth while postponing vaccination for another group until six weeks old. The WHO said this approach exposed infants to “potentially irreversible harm,” given that the birth-dose vaccine is a proven public health intervention with decades of safe use in more than 115 countries.
“Hepatitis B vaccination at birth prevents mother-to-child transmission in 70–95% of cases,” the WHO said. Infection at birth is the most common route to lifelong infection, with 90% of infected newborns becoming chronic carriers.
Guinea-Bissau currently administers the vaccine at six weeks, but authorities plan to roll out the birth-dose nationwide by 2028, in line with global standards. The WHO stressed that the trial could have accelerated this rollout but criticized the study’s scientific justification, ethical safeguards, and alignment with established research standards.
The trial, which was set to involve 14,000 newborns, was suspended last month after public outrage. Critics questioned why babies in Africa were being used for a study that would withhold a proven life-saving intervention.
The US health department overseeing the study is headed by Robert F. Kennedy Jr., who has previously raised doubts about vaccines despite publicly stating that he and his children have been vaccinated. Two months ago, a panel appointed by Kennedy voted to stop recommending hepatitis B vaccination for all US newborns, raising further ethical concerns.
The WHO reiterated that withholding a proven vaccine in a clinical trial is only acceptable when no effective treatment exists. For hepatitis B, the birth-dose vaccine is a critical, life-saving measure.
