A view of Ketchikan from the top of the Edmonds Street stairs. (Photo: State of Alaska)

The Ketchikan Emergency Operations Center reported a positive test for COVID-19 on Tuesday.

The man who tested positive has a history of travel to the Lower 48, the operations center said in a written statement.

“Upon experiencing symptoms of illness, the individual self-isolated and sought testing through a Ketchikan clinic. The individual is an employee of the Ketchikan Gateway Borough,” the statement said.

Related: State bans restaurant dining as Alaska’s confirmed coronavirus cases grow to 6

The borough said it has hired a commercial service for a thorough disinfection of the entire the White Cliff Building — the borough’s headquarters — including the outside areas of the building.

“Borough employees in direct contact with the individual will be self-isolating for a period of no less than 14 days. Employees who were not in contact with the individual may return to work sooner,” the borough’s statement said.

This is the fourth positive test for coronavirus in Alaska in a week. Two men who traveled to the Lower 48 tested positive Monday in Fairbanks. One of the Fairbanks patients was an employee at the University of Alaska Fairbanks and worked in an office at the O’Neill Building, on the UAF campus.

To be prudent, “we are temporarily closing the building, effective immediately,” UAF Chancellor Dan White said in an emailed announcement. “Occupants of the O’Neill Building are being asked to stay home and self-observe for 14 days.”

The first confirmed coronavirus case in Alaska was announced last Thursday. That patient was a cargo pilot who had only recently arrived in Anchorage.

Keep up with today’s news about coronavirus in Alaska with our collected coverage.

In Ketchikan, officials “will be working with Alaska Public Health and ensuring that we get word out to the public that we have a confirmed case,” said Abner Hoage, Ketchikan emergency manager and fire chief.

The state will begin contacting everyone who came in contact with the Ketchikan man, Hoage said.

Even healthy residents should be on the lookout for a fever, cough or trouble breathing, Hoage said.

“We want people to take even mild symptoms very seriously. The best thing that we can do, the way that we can have the most impact, is flattening the curve,” he said.

Those with symptoms should call their doctor for instructions instead of showing up at a clinic, where the virus could spread, he said.

KRBD reporter Eric Stone contributed to this story from Ketchikan. Liz Ruskin contributed from Anchorage.