Pennsylvania health and education officials are moving to close a window that allows young children to attend school for up to eight months before getting all their required immunizations.

That's a welcome step toward keeping kids healthy.Pennsylvania's rate of childhood immunization has dropped in recent years. At 87 percent, it's well below the 95 percent that health officials consider the minimum to prevent widespread contagion - such as the measles outbreak in Disneyland last year that quickly traveled beyond California, infecting 147 people in seven states, Mexico and Canada. All because a handful of unvaccinated people at the amusement park.The Lehigh Valley's immunization rate last year was 90 percent, above the state average. New Jersey's statewide rate was 95.6 percent.So why is Pennsylvania lagging behind? One reason is that it allows parents to declare a philosophical or moral exemption to childhood immunizations, as well as religious and medical exemptions. In the 2013-14 school year, the state granted about 8,000 exemptions, of which 3,342 were for philosophical reasons. While parents don't have to cite a specific reason, many objectors may have been reacting to a now-discredited medical study that purported to link childhood vaccinations to autism.Just 15 years ago, measles was believed to have been eliminated as a "homegrown" disease in the U.S., but that buffer has been breached. The U.S. Centers for Disease Control and Prevention reported 668 cases last year in 27 states, the highest level since the turn of the century.The easiest way to counter this is to have kids complete their measles-mumps-rubella treatments before they show up for kindergarten.Toward that end, Secretary of Health Karen Murphy and Secretary of Education Pedro Rivera have proposed that children be required to get their final dose (or have a physician-approved plan for completing immunizations) within five days after starting school, instead of the current eight-month grace period. Children would still have to have their first doses before starting school.Also, Murphy and Rivera want to add a pertussis (whooping cough) vaccine to the list, and require students starting 12th grade to get a meningitis shot. Parents would face stricter rules to prove their young children have had chickenpox and thus don't need that vaccine.These seem like common-sense ideas, but they must be reviewed by legislative and regulatory officials to make sure 1) they're all needed and 2) they'll have the intended effect of getting more parents to opt into, rather than out of, immunizations. The current law affects kids in public, private, charter and cyberschools.On another track, Pennsylvania should eliminate the philosophical exemption, allowing only religious and medical opt-outs, as most other states do.State Reps. Michael Schlossberg of Allentown and Becky Corbin of Chester County, along with state Sen. Daylin Leach of Montgomery County, have introduced bills to accomplish that, but the legislation has been mired in committees. It's time to act on this, to protect all children from preventable diseases, and move Pennsylvania toward a level of protection that is - unlike so many other problems in society, health and education - next to worry-free.- The (Easton) Express-TimesThe foregoing opinions do not necessarily reflect the views of the Editorial Board or Times News LLC.