Colorized scanning electron micrograph of a cell (blue) infected with SARS-COV-2 virus particles (red), isolated from a patient sample. (Photo: National Institute of Allergy and Infectious Diseases)

Ketchikan High School will be closed until at least Tuesday after a person associated with the school tested positive for COVID-19, district officials say in a statement. Preschools housed at the high school will also be closed.

The district’s other schools will remain open. Ketchikan High School students will learn remotely Monday.

News of the high school’s closure capped off a Halloween weekend that saw more than a dozen new cases. Ketchikan set new records for the number of active cases and the rate of new infections.

After announcing four new cases on Friday, local officials announced a total of 13 more on Saturday and Sunday. That brings the area’s active case count to 25 as of Sunday evening. Some 23 of those came within the last week.

That’s more than double the previous record of 10 new infections in a week. That was set back in March.

In a statement Thursday, Cape Fox Corporation announced it was tracking an outbreak among its employees. Mass testing of its workforce revealed more than a dozen cases. The Saxman-based Alaska Native corporation canceled planned Halloween parties and closed its five local restaurants through at least Friday, Nov. 6. Cape Fox says it’s planning to re-test its restaurant employees a day before the planned reopening.

Other Ketchikan restaurants announced their own voluntary precautions. Ocean View Restaurant closed pending tests for all of its employees. Several other businesses announced they’d take other measures to reduce the risk of spreading COVID-19.

Officials were able to link many of the new cases to the Cape Fox cluster. That’s good news for the community’s risk level, which recommends steps local officials can take to slow the spread. As of Sunday, the metric remains at level 2, or “moderate,” which means no mandatory restrictions for schools or businesses.