B.C. dentists are being strongly urged to cancel all but emergency services after several attendees at the Pacific Dental Conference in Vancouver tested positive for COVID-19.

About 15,000 people attended the annual conference at the Vancouver Convention Centre from March 5 to7.

"I was not aware of the dental conference. We were not consulted on that. And it was at a time when I was advising that medical conferences in particular should not be held," said provincial health officer Dr. Bonnie Henry. "I’m very disappointed in that fact."

At least four of B.C.’s COVID-19 cases have been traced back to the conference as well as several others from Alberta and Ontario.

"I suspect in retrospect there was more than one person there that was incubating or sick with the virus and passing it on to others," said Henry. "This just became apparent when we looked at some of the exposure yesterday of people who became ill over the weekend."

So Henry is now ordering everyone who attended the conference to self-isolate immediately, calling the matter urgent.

"They should not be at work. They should not be at school. They should not be around others. This is the critical time where we’re starting to see people turning up with illness related to this conference," said Henry.

Hours after the provincial health officer ordered the conference attendees to self isolate, the B.C. College of Dental Surgeons posted a letter on its website ordering its members to comply. And it’s strongly suggesting dentists cancel all non-essential and elective dental procedures. The college represents more than 10,000 dentists, dental therapists and certified dental assistants.

Dr. Henry hopes patients were not exposed to the virus by people who attended the conference and then went to work.

"Dentists and dental hygienists are health care professionals, and I would hope that none of them would work if they were ill," said Henry. "Dentists also take infection prevention and control precautions within their offices."

Dentists are being urged to stay open for emergencies, but it will be up to each individual office. Patients are being urged to call their dentist if they think they’ll need dental work in the coming weeks.