The hold will likely delay trial results, and scientists say the pause is proof that safety protocols in clinical trials are working as they should.

Some researchers express skepticism given the lack of data about the vaccine’s safety and efficacy, and the country plans to vaccinate healthcare workers, teachers, and others even before testing is complete.

Vaccine experts divided on whether that level of protection is too low or too demanding.

Engineered Plasmodium parasites form the basis of two experimental malaria vaccines that showed safety and encouraging immune responses in clinical trials.

The idea of deliberately infecting volunteers with SARS-CoV-2 has garnered significant attention as a potential avenue to speedier development, as the World Health Organization weighs in with recommendations.

Rick Bright will no longer head the Biomedical Advanced Research and Development Authority and will instead work at the National Institutes of Health on diagnostics for SARS-CoV-2 infection.

Stay up-to-date on the progress of dozens of vaccine candidates that are currently undergoing clinical testing.

The study, conducted in Malawi, Kenya, and Ghana, did not obtain informed consent from each parent whose child participated, but rather considered consent “implied” because of the particular experimental design.

TAK-003 appears to avoid the safety issues seen with an existing vaccine, but experts say a longer evaluation is needed.