Jenzy Guzman wears a mask to help prevent the spread of the coronavirus while loading his truck while making deliveries to restaurants in the Old Port, Tuesday, Oct. 13, 2020, in Portland, Maine. Credit: Robert F. Bukaty / AP

Two coastal counties that have seen fewer than 100 cases each throughout the coronavirus pandemic have seen the steepest rise in cases over the past week.

The seven-day rolling averages of new COVID-19 cases have jumped the most in Washington and Knox counties as Maine has experienced a surge in new virus cases following a summer during which the state largely kept the virus in check. The state has now set new case records for the second day in a row, and the uptick in cases is happening virtually everywhere in the state.

In Washington County, the seven-day average of new cases hit 4.85 as of the end of Tuesday, up from 0.43 a week earlier. The spread of the virus prompted Calais City Hall to close for three days and Calais Elementary School to switch to fully remote instruction until Nov. 9. An outbreak at Second Baptist Church in Calais had grown to 27 cases as of Wednesday.

Washington County has recorded 60 cases since the start of the pandemic in March, and it still has Maine’s fifth lowest infection rate, according to Maine Center for Disease Control and Prevention data.

Knox County saw its average of new daily cases jump to 2.86 as of Tuesday, up from 0.86 a week earlier. The county this week has seen its cases inch up as an assisted living facility — Woodlands Memory Care in Rockland — has become the site of a coronavirus outbreak that had grown to 12 cases on Wednesday.

Knox County has still seen just 82 cases since the start of the pandemic, giving it the seventh lowest infection rate in the state.

Use the chart below to see how new cases have trended in Maine and its 16 counties since April. The chart shows a seven-day rolling average of new daily cases, which smooths out day-to-day fluctuations.