The state’s Board of Elementary and Secondary Education — after previously indicating each district would make its own determination — on Tuesday announced a statewide mask requirement for all public K-12 students and staff through at least Oct. 1.

Education commissioner Jeffrey Riley said he will reassess the mandate on Oct. 1, looking at not just vaccination statistics but infection and hospitalization totals. He added that more details and guidance will be shared with districts this week.

Hopkinton’s School Committee already voted last week to open the school year with the requirement that students and staff wear face coverings.

The mandate comes amid a surge in COVID-19 cases due in large part to the delta variant.

State officials indicated that they hope the mask mandate spurs an increase in vaccinations. As an incentive, on Oct. 1, middle schools and high schools in which 80 percent of students and staff are vaccinated can lift the mask requirement for those who are vaccinated. However, Riley indicated that this plan might need to be altered.

“We also cannot completely rule out the possibility that masks may be required intermittently throughout the year, based on the trajectory of the virus and any new emerging variants,” he said.

Recent statistics indicate more than 95 percent of Hopkinton residents aged 12-19 have been at least partially vaccinated, although the percentage likely is a little lower due to the chart using old census population totals. No data has been shared on teacher/staff vaccinations.