When a child gets chickenpox, he or she isn’t the only one affected. That’s obvious from recent events at the Rowe School in Yarmouth, where the diagnosis of two children with the highly contagious disease has prompted school officials, citing state law, to send five unvaccinated students home.

Maine has one of the nation’s highest rates of unvaccinated kindergarten students, according to a U.S. Centers for Disease Control and Prevention report released last week. Nationally, parents of 1.6 percent of kindergartners chose to forgo immunizations for nonmedical reasons during the 2015-16 school year. In Maine, the nonmedical kindergarten opt-out rate that year was 4 percent, or eighth highest in the country.

Rowe School’s 2015-16 opt-out rate was 3.6 percent – not much better than the state average. But this year’s opt-out rate is under 2 percent, according to Superintendent Andrew Dolloff, so relatively few Rowe students are at risk of being infected with chickenpox.

That’s important, because Rowe’s 200 students are all in either kindergarten or first grade. Consistent school attendance early on has been shown to help children both academically and socially. Young students who miss even just two days of school a month have a harder time catching up than others and are more likely to leave school altogether later on. Early school absenteeism has even been linked with poor workplace habits in adults.

Five unvaccinated children were sent home from Rowe for 16 calendar days, though two of those students have had their first chickenpox shot and will be allowed to return when they get their booster vaccination.

If the chickenpox diagnoses had occurred elsewhere, dozens of unvaccinated students would have had to stay home. There are schools in Maine with much lower vaccination coverage than Rowe.

During the last school year, at least 40 Maine schools had a kindergarten or first grade opt-out rate of 10 percent or more, reducing herd immunity protections and putting them most at risk of an outbreak. Schools in Gray, Kennebunkport and Hancock are among those where the rate of unvaccinated kindergartners or first graders reached or exceeded 20 percent in 2015-16.

We’ve long been aware that immunization protects our physical health. It’s becoming clearer that vaccine coverage also prevents the disruptions that knock young students off track – another benefit to the community, and a lesson worth emphasizing as Maine works to get childhood immunization rates where they belong.