In this April 10, 2020, file image made from video, a lab technician dips a sample into the Abbott Laboratories ID Now testing machine at the Detroit Health Center in Detroit. Federal health officials are warning about potential accuracy problems with the rapid test for COVID-19 used at thousands of hospitals, clinics and testing sites across the U.S., including the White House. Credit: Carlos Osorio | AP

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The Scarborough location of a company that manufactures tests that quickly identify whether someone has the coronavirus is now the site of a virus outbreak, according to Maine’s public health agency.

Abbott Laboratories in Scarborough has seen 23 coronavirus cases among 679 employees since mid-April, with five detected since May 31, Maine Center for Disease Control and Prevention Director Nirav Shah said Tuesday.

The five most recent cases prompted the state to open an outbreak investigation, Shah said. Disease investigators will look into whether the virus has spread at the Abbott location, or whether employees have potentially brought the virus in from outside. While the company has seen cases since mid-April, there had not been enough concurrent cases until recently to warrant an outbreak investigation.

Abbott spokesperson Scott Stoffel said in an email that nearly every employee who tested positive was asymptomatic when tested. Those individuals self-quarantined upon testing positive, he said.

Stoffel said two of the five employees tested since May 31 were new employees who had not started working for the company. He said there is no evidence that employees got sick from their workplace.

But tracking workplace outbreaks can be challenging because there are many potential sources of infection in a single day, Shah said, such as when workers get in an elevator with others or pop into a colleague’s cubicle. He said the state is focusing on the shifts people work in order to get a sense of when sick individuals might have overlapped.

The company attracted national attention earlier this spring for developing a coronavirus test that could produce results in minutes. Experts have questioned the accuracy of the tests, but the company has chalked those discrepancies up to problems with transporting test samples. Maine has said it double-checks results from some negative tests conducted with Abbott materials. Shah has said the state has confidence in positive results the Abbott test produces.

The state had touted the test’s usefulness in conserving protective gear for hospitals and places where employees were more likely to come in contact with a sick person. In April, Maine received 15 testing machines it ordered but only a fraction of the materials needed to run the tests that it had ordered.

The company has been testing its employees weekly since mid-April and is now testing construction workers that have been at the facility, Shah said. He said the company is following best practices recommended by the CDC, including distributing protective gear to employees and employing social distancing practices.

Shah praised the company for “taking this early, proactive step toward testing” all employees.

“When you go out and look for things in public health, you find them,” he said.

Stoffel said all tests are “quality controlled” before release and that the labs are cleaned by those who work in them, minimizing the number of people moving in and out. The company routinely cleans general areas, and the lab’s production area is deep-cleaned weekly, he said.

Maine had over 40 active outbreaks last week, with nursing homes seeing some of the largest numbers of cases but workplaces outside of health care also reporting large case numbers.

Shah on Tuesday announced four other new outbreaks in addition to Abbott’s. Two were at long-term care facilities — three cases at Montello Manor in Lewiston and five at Serenity Residential Care in Gorham — while another was at Support Solutions in Auburn, an organization that provides support services to adults with development disabilities and reported four cases. An additional outbreak of seven cases has been reported at the Nichols Portland manufacturing plant in Portland.

BDN reporter Charles Eichacker contributed to this story.

Watch: What Maine is doing to expand contact tracing

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