Maine has adopted a new vaccine requirement for seventh-grade students.
The Portland Press Herald reports that starting this September, seventh-grade public school students will be required to receive a second dose of Tdap, a vaccine that protects against tetanus, pertussis and diphtheria.
The state Department of Health and Human Services adopted the rule last week. The newspaper reports the state will become the 48th in the U.S. to require the middle school booster shot.
Maine has one of the highest rates of pertussis - a contagious respiratory disease - in the country. Public health experts say improved vaccination coverage should help reduce the number of cases.
State law allows parents to opt out of required immunizations for their children on religious or philosophical grounds by signing a form.