WASHINGTON — An advisory board said Friday that ethical issues need to be resolved if the anthrax vaccine is going to be tested in children to be sure it’s safe and to learn the proper dose in case it’s needed in a terrorist attack.

It has been widely tested on adults but never on children.

The question is whether to do tests so doctors will know if children’s immune systems respond to the shots well enough to signal protection. The children would not be exposed to the potentially deadly bacteria.

The National Biodefense Science Board said Friday a separate review board should look into the ethical issues of doing such tests in children. If that is completed successfully, the panel, said, the Department of Health and Human Services should develop a plan for a study of the vaccine in children.

A big question is whether parents would sign up their children to test a vaccine when there is no immediate threat. It’s not possible to get anthrax from the vaccine, but there are side effects. In adults, shot-site soreness, muscle aches, fatigue and headache are the main ones, and rare but serious allergic reactions have been reported.