Families who, last year, were so eager to get children back to school for in-person learning are now confronting a gnawing fear each morning. Their child could be exposed to COVID-19 in the campus environment and be sent home, with the possibility that they, too, could become sick.

Schools have struggled to provide all the layers of protection that they’d hoped to incorporate, back when planning did not account for the ultra-contagious delta variant of the virus, which had yet to take hold.

But take hold it did, with the result that almost all the current cases of infection with this coronavirus is due to its most transmissible and, according to some studies, most virulent mutation. With increasing activities and tourism arrivals in early summer, the community spread widened — just before the return to school for the fall term.

There is one avenue for further shielding campuses, one that state education administrators should allow, with proper regulatory controls: expanding the vaccine mandate, starting with the older students in high schools.

In addition, vaccines for all students who are both eligible and willing should be made much more accessible to them in mobile clinics at or near school campuses. These should be distributed along with COVID-19 testing to be conducted at more sites statewide.

Regular and frequent testing will be crucial to containing the clusters of infections cropping up at some schools. The Hawaii Board of Education (BOE) on Thursday heard complaints from many parents and teachers about the lack of widespread surveillance testing on campuses, which is one of the public school system’s greatest vulnerabilities.

Fortunately, a federally funded Operation Expanded Testing program is gearing up, with 59 public schools and 13 charter ones already conducting the tests. Some 161 of 257 public schools are now registered, but more must be added.

On the immunization front, three different vaccines were initially given emergency-use authorization, available to those age 12 and older. The formulations from Johnson &Johnson and Moderna currently remain in that category.

But the third vaccine, from Pfizer/BioNTech, in August received full approval from the U.S. Food and Drug Administration for injection in persons age 16 and older.

That means the Pfizer shot officially has the same level of authorization as the vaccines for other diseases that already are required for attending school. Nonetheless, Hawaii’s public school officials are leaving the decision on student vaccine mandates to the state Health Department, Keith Hayashi, the interim superintendent, told the school board.

Hearing that, BOE member Bruce Voss rightly countered that there should be more urgency applied to the issue. Hayashi did say that he would embark on the discussion with health officials.

The public should hold him to that pledge. The process of pushing Hawaii into a safer level of immunization will require that more attention be paid to the younger demographic, starting with those 16 and up.

This is not nearly as aggressive a stance as the Los Angeles Unified School District has taken: Officials there have mandated vaccinations for students age 12 and up, by Dec. 19.

Given that full FDA approval probably is not forthcoming for the younger group until year’s end, starting first with the mandates for older teens would be less vulnerable to legal challenge. The state should be holding hearings and taking other steps for adding the COVID-19 vaccine to the list already mandated by state law, applying it to the over-16 age group.

Encouragingly, vaccination rates have begun to climb significantly as mandates have rolled out, and in response to the general concern about the delta surge. But the greatest room for improvement is among the young.

The Department of Health (DOH) COVID-19 data dashboard shows that of the 12- to 17-year-olds, all eligible to be immunized, only 59.4% are fully vaccinated. The rate is lagging particularly in Maui (48.2%) and Hawaii island (49.8%),

Maui was one focus of concern identified in Thursday’s DOH cluster report, which cited an August investigation of 26 cases in a public elementary school there. And the problems are not limited to public schools. A Kauai private school was the location for a cluster of 45 cases.

State health officials recognize what’s behind such spikes: “With high community transmission,” the report stated, “cases among students and staff are expected.”

Maui County has the state’s lowest overall vaccination rate, with 59% of the total population completing their shots. Children easily can contract the disease from unvaccinated family members; bringing up the overall community vaccination levels is the key strategy for making schools safer.

The pandemic has compelled a stringent approach to immunization, much more so than anyone envisioned at the outset. But statistics — including infection rates — don’t lie. Any plan for a healthy school environment will require vaccinations, and students must be part of that solution.