Members of the education committee for the House of Representatives, in effect, endorsed the state’s current approach on Tuesday. By a voice vote, they advanced a heavily amended version of the bill that now calls for only technical changes to Mississippi’s law, which has been largely untouched since the late 1970s. The law requires all children in public and private schools to have certain immunizations, including for chickenpox, hepatitis B and measles. Generally, children must have the vaccines by the time they are in kindergarten.

Mississippi — one of the states with the worst rates of smoking, obesity and physical inactivity — is seldom viewed as a leader on health issues. But it is one of two states that permit neither religious nor philosophical exemptions to its vaccination program. West Virginia is the other. Only children with medical conditions that would be exacerbated by vaccines may enroll in Mississippi schools without completing the immunization schedule, which calls for five vaccines.

For the 2013-14 academic year, Mississippi reported that nearly all of its 45,719 kindergarten students had been adequately immunized, and the state’s measles, mumps and rubella vaccination rate was about five percentage points higher than the national median of 94.7 percent.

For kindergartners that year, Mississippi approved just 17 medical exemptions, the Centers for Disease Control and Prevention said. Neighboring Arkansas, which had about 3,100 fewer kindergarten students than Mississippi that year, recorded 24 medical exemptions, along with 468 religious or philosophical exemptions.