With Connecticut experiencing a statewide surge in COVID-19 cases, the state Department of Public Health recommended Friday that residents consider resuming wearing masks when in public indoor spaces.

The department, in a news release issued late in the afternoon, cited the U.S. Centers for Disease Control and Prevention’s latest county-by-county assessments of COVID-19 levels, which found six of Connecticut’s eight counties ― Hartford, Litchfield, Middlesex, New Haven, Tolland and Windham ―- have “high” rates of the disease.

New London and Fairfield counties have “medium” COVID-19 rates, according to the CDC.

In New London, a Lawrence + Memorial Hospital spokeswoman said Friday the hospital was treating 22 COVID-19 patients while its Yale New Haven Health affiliate, Westerly Hospital, was treating six patients with the disease. The numbers were the hospitals’ highest since September, according to the spokeswoman, Fiona Phelan.

On Thursday, Gov. Ned Lamont’s weekly update of COVID-19 statistics showed that in the previous seven days, 4,750 new cases of the disease had been detected among 27,365 tests ― a positivity rate of 17.4%. An additional 47 people had been hospitalized with the disease, bringing the number of those currently hospitalized to 761.

In the previous seven days, 33 deaths had been associated with the disease, raising the total number of state COVID-19 deaths since the March 2020 start of the pandemic to 11,803.

The state’s COVID-19 positivity rate has been climbing each week since Nov. 23, when it was 7.2%.

The state health department reported that as of Wednesday, 311,460 cases of COVID-19 had been found among fully vaccinated people in the state, representing 10.4% of the nearly 2.8 million people in the state who are fully vaccinated.

The CDC began its county-by-county tracking of “community levels” of the disease last February, relying on a combination of three metrics: new COVID-19 hospital admissions per 100,000 population, the percentage of staffed inpatient beds occupied by COVID-19 patients, and new COVID-19 cases per 100,000 population.

Community-level designations of “low,” “medium” and “high” are meant to indicate the potential for impact on health systems.

Because all eight Connecticut counties are either in the “high” or “medium” categories, the state health department recommends all residents consider wearing masks in public indoor spaces. People who are at high risk for severe illness should consider additional measures to minimize their exposure to COVID-19 and other respiratory illnesses, the department said.

Residents also are advised to stay up to date with COVID-19 vaccines and get tested if they have symptoms of the disease. Links to COVID-19 resources in the state can be found at www.ct.gov/coronavirus. Free self-test kits are available from the federal government at www.covid.gov/tests.

b.hallenbeck@theday.com