Top Democrats on the House Energy and Commerce Committee requested a briefing from the Centers for Disease Control and Prevention (CDC) on Thursday, October 22, 2026, regarding the agency's $1.6 million funding of a controversial hepatitis B vaccine trial in Guinea-Bissau. The trial, led by Danish researchers, proposed randomly assigning half of approximately 14,000 newborns to receive the vaccine at birth while the other half would receive their first dose at two months of age.
The funding was awarded last year to researchers from the University of Southern Denmark to assess the "non-specific" health effects of the vaccine birth dose. While the World Health Organization (WHO) has recommended the birth dose to prevent chronic infection, a federal advisory panel recently voted to stop recommending the shot for all U.S. newborns. That change is currently halted by a court injunction in Boston.
Critics of the study, including WHO Director-General Tedros Adhanom Ghebreyesus, have described the trial design as unethical because it involves withholding a proven vaccine in a region where nearly 19% of adults are infected with hepatitis B. Lead researcher Christine Stabell Benn defended the study, stating that no child would receive fewer vaccines than required by current national policy in Guinea-Bissau, which does not currently administer a birth dose but plans to do so by 2028.
For the public, this investigation highlights a shift in federal vaccine policy under the Trump administration, specifically regarding the recommendation for the hepatitis B birth dose. If the trial were to proceed, infants in Guinea-Bissau would be placed into two groups: one receiving the vaccine at birth and another waiting until two months of age. Lawmakers stated that infants who do not receive the vaccine at birth face a higher risk of chronic infection, which can lead to liver failure or death.
The outcome of this inquiry may set a precedent for how the CDC manages international clinical trials and the transparency of its funding decisions. The status of the trial remains unclear; while the researchers and the Department of Health and Human Services (HHS) maintain it is moving forward, Guinea-Bissau’s government previously indicated the study was suspended or terminated. The Democratic lawmakers have requested a staff-level briefing by November 6, 2026.