A person lawfully administering a drug or vaccine shall have the immunity from liability described under § 5-629(b) of the Courts and Judicial Proceedings Article. If the Secretary or a designee of the Secretary finds that a proposed immunization project would conform to good medical and public health practice and gives written approval for the project to be administered in this State, a physician, nurse, or other person participating in the project shall have the immunity from liability described under § 5-629(c) of the Courts and Judicial Proceedings Article.