Masks will remain required in Massachusetts public schools until at least Nov. 1, the Department of Elementary and Secondary Education said in guidance issued to districts and published Monday

The Board of Elementary and Secondary Education in August authorized Commissioner Jeff Riley to require masks for students age 5 and up and school staff through at least Oct. 1, and Riley on Monday extended the requirement through at least Nov. 1.

The board in August also declared that "exigent circumstances" exist that hinder students' ability to safely attend classes, a move that allows Riley to issue health and safety requirements for districts.

The mask plan Riley put forward in August allowed for middle and high schools where at least 80 percent of students and staff have been vaccinated against COVID-19 to be able to lift the mask requirement in October, for vaccinated individuals only. Kids age 12 and under are still not eligible for the shots.

Under the latest guidance, as of Oct. 15, in schools that submit to the state an attestation form demonstrating a vaccination rate of 80 percent or higher among students and staff, vaccinated individuals will no longer need to wear masks.

The department also posted additional details on calculating the 80 percent vaccination rate, which says, "Schools should determine a method to collect proof of COVID-19 vaccination for all eligible staff and students."

School districts last week reported 2,236 new COVID-19 cases among students and 318 in staff. The combined total of 2,554 during the week of Sept. 16-22 is up from the 1,420 logged over three days in the previous week's report.