The US Centers for Disease Control and Prevention is moving to revive a controversial study in Guinea-Bissau that would test the timing of the hepatitis B vaccine in newborns, after the University of Southern Denmark granted ethics approval for the project this month.
The study, to be run by researchers linked to the Bandim Health Project, has been contested for years because it involves delaying a proven vaccine dose for some infants in a region where hepatitis B is widespread. Guinea-Bissau’s own authorisation for the work is still being awaited, according to reporting on the approval.
Former CDC officials and independent academics condemned the revival in strong terms, arguing that the earlier institutional review had judged the project unethical and that experimenting with the timing of a birth dose risks preventable infections. An October 8 public statement by concerned scientists and advocates called the decision to proceed indefensible.
Supporters of this line of research have argued in the past that questions about how vaccines perform in high-burden settings deserve rigorous study, though the current protocol’s critics say the central question — delaying protection — is precisely the problem.
Health agencies stress that hepatitis B vaccination at birth is a cornerstone of preventing lifelong liver disease, and the dispute has become a test of how far wealthy-country funders can go in testing schedules abroad. For now, the project remains in procedural limbo, approved in Denmark, criticised in Washington and undecided in Bissau.
Hepatitis B is a leading cause of liver cancer worldwide, and infection at birth carries the highest risk of lifelong chronic disease, which is why global health bodies recommend a first dose within 24 hours of delivery. In high-burden countries, that birth dose is often the difference between protection and infection passed from mother to child.
That epidemiology is what makes the Guinea-Bissau protocol so contentious: critics argue the study’s central comparison has already been answered by decades of evidence, while ethics boards must weigh whether local conditions justify revisiting it. The controversy is likely to follow the project whatever Bissau decides.
