Newfoundland and Labrador is reporting no new cases of COVID-19 on Sunday as public health officials continue investigating the source of a cluster of five cases in the Eastern Health region. 

As part of its investigation, public health is asking anyone who worked at or visited any of three establishments in downtown St. John's, during the dates and times listed below, to call 811 to arrange testing:

• The Duke of Duckworth, 325 Duckworth St., on Wednesday, Jan. 20 from 3:30 p.m. to closing time.
• The Rose and Thistle Pub, 208 Water St., on Wednesday, Jan. 20 from 4:30 p.m. to closing time.
• Piatto Pizzeria & Enoteca, 377 Duckworth St., on Friday, Jan. 22 from 6 p.m. to closing time.

People can also arrange testing by completing the online self-assessment and referral tool available here. 

All those who get tested must self-isolate until they receive a negative test result, the Department of Health said in a media release.

During Friday's provincial briefing, Chief Medical Officer of Health Dr. Janice Fitzgerald said identifying specific businesses wasn't necessary at the time.

That changed on Sunday, however.

"Through the course of the investigation, new information regarding potential sources of exposure in the establishments came to light, which made it necessary for public health to issue the advisories today," the Health Department wrote in a statement to CBC News.

When reached by CBC News on Sunday afternoon, a spokesperson for Piatto said they were not willing to comment yet. Posts on the restaurant's social media pages said it would be closed Sunday.

Both the Duke of Duckworth and the Rose and Thistle Pub were open Sunday. 

Contact tracing at St. John's gym

On Thursday, Max Fitness was notified that someone who attended a fitness class at the New Cove Road location on Jan. 14 had tested positive. 

Contact tracing had already been completed, and Max says it has stringent physical distancing and cleaning protocols, so public health instructed them to continue with operations as usual. 

CEO Steve Ash said while the situation is concerning, he trusts the advice he gets from medical experts. 

"You do get very concerned, especially when you've been notified that it occurred two weeks prior," he said.

"You sort of think, is there anything else that we should be doing? Some other organizations in the city and companies in the city had to shut down. And I'm not familiar with why that was."

Ash said it's ultimately the experts at public health who know the proper course of action.

"As a CEO, I have to rely heavily on the experts. We learn and we educate ourselves as much as we can in terms of what we should and should not be doing. But at the end of the day, the folks that are making decisions for public health are obviously far more educated and informed on making these sorts of decisions."