| The potential change outlined in a statement says all new vaccines will be required to undergo placebo testing, a procedure in which some people receive the vaccine and others receive an inert substance — such as a saline shot — before the results are compared. The Department of Health and Human Services says the move will increase transparency but medical experts fear it could limit access to vaccines and undermine the public’s trust in immunization depending on how it is implemented. HHS did not fully clarify how the change would work and for which vaccines the testing would apply. | 
