The discovery of Legionella bacteria last week prompted the brief closure of three Maryland state office buildings in Baltimore, forcing employees to work from home, according to a spokesperson for the Maryland Department of General Services.

State officials said they did not know the origin of the bacteria, which was discovered after periodic environmental testing. No employees have reported any illnesses because of exposure to the bacteria, the spokesperson said.

On Friday, periodic environmental testing at 201 Preston St. at the State Center Complex showed a slight elevation for legionella bacteria, which can cause Legionnaires’ disease, a serious type of pneumonia, according to the Centers for Disease Control and Prevention. That building was closed over the holiday weekend, and workers are back in the office.

“We got an outside contractor to start work over the holiday weekend,” Director of Communications Eric Solomon told The Baltimore Sun. “They did a water flush. They sanitized the pipes and did a retest.”

At 300 W. Preston St., Legionella bacteria levels were in the Environmental Protection Agency’s normal range, but the building was closed on Wednesday for the flushing and sanitizing of pipes. Employees can return Thursday.

In addition, the state’s building at 301 Preston St. was tested in September and was normal. As a precaution, however, that building is closed to staff Wednesday while contractors perform the flush and sanitation to the pipes. Workers can return Thursday.

“It’s not closed because of any threats of bacteria. It’s closed because the water is being shut down,” Solomon said.

The only other building in that State Center Complex, 1100 N. Eutaw St., will be tested Monday.

The State Center Complex is the headquarters for various agencies including the Department of General Services, Maryland Department of Health, Department of Budget and Management, Tax Court, Disabilities Relay Group and Department of Labor.

The Maryland Department of Health advised workers not to drink the water until the Department of General Services gets the results back from the retest.

The Department of Health also recommended that workers routinely wash their hands with warm water and soap and sanitize. The state provided water bottles for any staff in the building.

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