Open this photo in gallery B.C. Provincial Health Officer Bonnie Henry, seen here on March 14, 2020, said this week that at least four recent confirmed cases, and possibly more, are linked to the conference and that all attendees should self-isolate immediately. DARRYL DYCK/The Canadian Press

The organizers of a dental conference that’s blamed for a “significant” number of new coronavirus transmissions say they had consulted with health officials prior to the event and were given a green light to proceed.

B.C. Provincial Health Officer Bonnie Henry said this week that at least four recent confirmed cases, and possibly more, are linked to the conference and that all attendees should self-isolate immediately, until March 22. An estimated 15,000 people attended the conference at the Vancouver Convention Centre on March 5 through 7.

“We also know that cases have been identified from that conference in other provinces across Canada,” Dr. Henry said, naming Alberta and Ontario as examples. “My instructions are to anybody who was at that dental conference … to self-isolate immediately. They should not be at work, they should not be at school, they should not be around others.

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"This is the critical time, where we’re starting to see people turning up with illness related to this conference.“

The College of Dental Surgeons of BC on Monday “strongly recommended” that all elective and non-essential dental services be suspended immediately. The recommendation is in response to public health guidance about the pandemic, the college said, and is not necessarily a reaction to the exposure at the conference.

Organizers of the event – the British Columbia Dental Association and the Pacific Dental Conference – have been blamed for holding the conference during the fast-moving novel coronavirus situation in B.C.

But a statement issued by the president of the BCDA said the association “collaborated closely with several provincial health agencies on a range of issues to mitigate exposure,” respected all policy direction received, and discussed the conference with Provincial Health Services Authority staff on Feb. 24.

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“All parties were aware when the PDC was scheduled,” James Singer said in the statement. “At no time was the PDC asked by any public health representatives to halt the conference.”

The Pacific Dental Conference is one of the largest gatherings of its kind in North America. This year, more than 200 sessions were held and more than 700 exhibit booths were set up.

Speaking at a news conference on Tuesday, Canada’s Chief Public Health Officer, Theresa Tam, used the conference as an example of how quickly a virus can spread in large gatherings.

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On March 12, Vancouver Coastal Health issued a notification about the conference, saying that a person who attended the conference for two hours had since tested positive and that the risk to others was "extremely low."

However, the health authority later learned that “a number” of people at the conference were sick with the disease the virus causes, COVID-19, and four days later issued another notification urging all participants to self-quarantine until March 22.

“We subsequently learned there were others, which led to Dr. Henry’s advice and our revised statement to all attendees,” VCH spokesperson Matt Kieltyka wrote in an e-mail.​

Shannon Gu, manager of a dental clinic in Burnaby B.C., said she was furious to hear that a number of attendees of the event had tested positive for the new coronavirus.

Ms. Gu said she had warned the BC Centre for Disease Control, BCDA and PDC about the risk of holding such a big event, but she said her advice was ignored.

In an e-mail to all three agencies, which was viewed by The Globe and Mail, Ms. Gu listed several recommendations, including asking all attendees to wear a face mask and keeping the crowds to less than 2,000 people a day.

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In an e-mailed response to Ms. Gu, Bill Wong with the BCCDC said the centre wasn’t involved in the conference and deferred to other organizations to respond. Ms. Gu said she never heard back from PDC.

The PDC did not respond to The Globe’s request for comment. The BCCDC didn’t immediately return a call asking for comment.

Ms. Gu added that she and some of her colleagues were shocked by the B.C. dental college’s decision to suspend non-essential dental surgeries.

“They have to rearrange their patients," she said. "Lots of things have to be stopped suddenly and they have to apply for EI [employment insurance] for many of their staff. … Many unknowns are awaiting.”

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