Staff photo by C.B. Schmelter / Tape is used to mark off lines at the Volkswagen Conference Center on Wednesday, May 20, 2020 in Chattanooga, Tenn. The conference center is being used as a screening room as employees at the assembly plant return to work following a nearly two month shutdown due to the coronavirus.

This story was updated at 6:03 p.m. on Friday, June 12, 2020, with more information.

Volkswagen Chattanooga reported on Friday that it has confirmed 12 cases of the coronavirus among its employees, contractors and suppliers since May 17 when the factory resumed production.

The most recent case was last in the plant on May 28, the company said.

"To date, all positive cases are the result of outside exposures," the company said. "When a positive case is confirmed, CDC protocols are followed, and all general areas that may have been exposed to this individual received additional cleaning and disinfecting."

The company said that contact-tracing is conducted, and those meeting close-contact parameters are tested, and all individuals with positive test results are placed on medical leave in quarantine for the recommended 14 days.

"Per protocol, badge access is deactivated. The individual(s) cannot return to the plant until given medical clearance," the company said.

Volkswagen Chattanooga plant workers returned after a nearly two month shutdown due to the coronavirus.

The company instituted an array of changes for the return related to employee safety.

Tom du Plessis, Volkswagen Chattanooga's chief executive, said when the plant was reopening that the "health and safety of everybody in the factory is really critical."

VW said it took about 90 new safety measures. With all the safety steps, du Plessis said the plant was taking it slow and starting at just 50% production. He expected to be up to full production sometime this month if all went well.

Also on Friday, Volkswagen AG's said that its worldwide group sales of vehicles dropped in North America and in all regions except China in May amid the coronavirus pandemic, according to Marketwatch.

May sales globally fell 34% from a year earlier to 609,400 vehicles, Marketwatch said. In North America, the German automaker posted a 39% drop to 52,800 vehicles compared to a year ago, but in China, sales grew 5.7% to 330,300.

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