Powerful federal advisers this week are expected to make a controversial change to how babies are immunized against hepatitis B, and to question how pediatricians inoculate children against more than a dozen other infectious diseases, including measles, mumps, whooping cough and polio.

The Centers for Disease Control and Prevention's Advisory Committee on Immunization Practices (ACIP) is convening Thursday and Friday for a closely watched meeting to rethink fundamental elements of the childhood vaccination schedule, which has protected children from dangerous diseases for decades.

The potential changes are welcomed by allies of Health and Human Services Secretary Robert F. Kennedy Jr., who has long questioned the safety and effectiveness of vaccines.

"We're now starting to see truth

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