A US CDC-funded hepatitis B vaccine trial in Guinea-Bissau has been suspended pending regulatory and ethics agreement.[1][2][3] The study planned to include 14,000 newborns, with half given the vaccine at birth and half at 6 weeks, as is the current standard in the country.[1][2][5] The goal was to track overall mortality, hospitalizations, atopic dermatitis, and neurodevelopment over five years.[2][5] African scientists and the Africa CDC called the study unethical due to the known effectiveness of the vaccine at birth in an endemic area where 90% of newborns exposed at birth acquire chronic infection.[1][2] In Guinea-Bissau, hepatitis B is common, with approximately 11% of children infected by the age of 18 months and 20% of the population being carriers.[5] The six-member ethics committee did not meet before approval.[2] The Ministry of Health plans universal vaccination at birth in 2027-2028, the study would end before then.[1][3][6] US officials insist on proceeding after assessment.[1][3]