Nearly 15,000 people who attended a dental conference in Vancouver in early March have been told to self-isolate immediately by B.C.'s provincial health officer who said multiple cases of coronavirus have been traced to the event.

On Monday, Dr. Bonnie Henry said 30 additional cases of COVID-19 have been confirmed in B.C. since Saturday, bringing the total in the province to 103.

Henry said at least four of those new cases are related to an infected person who attended the Pacific Dental Conference, held at the Vancouver Convention Centre March 5 to 7.

Henry said cases of COVID-19 identified in other areas of the country have also been traced back to the Vancouver conference.

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According to Vancouver Coastal Health, the initial person who has tested positive for COVID-19 attended the conference on March 6 between 2 p.m. and 4 p.m.

Henry says anyone who attended the event must self-isolate for 14 days.

"They should not be at work. They should not be at school. They should not be around others," said Henry.

If symptoms develop, people are asked to contact 811 or their health care provider. Only if symptoms are severe, such as shortness of breath or chest pain, should British Columbians call 911 or go to the Emergency Department.

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Self-isolated individuals should not go to work, school, any public areas or use public transport or taxis.

Vancouver Coastal Health issued a release on March 12 saying the risk to participants was extremely low and attendees could continue to work as long as they did not develop symptoms.

Henry reversed that advice with Monday's announcement.

Record attendance

Dr. David Ciriani, president of the Kamloops and District Dental Society, said the conference set records this year for attendance.

"Traditionally, attendance there is probably about, oh, just about 90 per cent of the dentists in the province," Ciriani said from his home, where he is now in self-isolation.

Ciriani and many of his colleagues are shutting down their offices, suspending elective procedures and trying to find alternatives — namely any dental staff who didn't attend the conference — for patients who are dealing with severe pain or infection.

"The degree of dental services available across the province is going to be really curtailed," he said.

"This is uncharted territory for all of us."

Suspending services recommended

In a statement, the College of Dental Surgeons of British Columbia (CDSBC) said it recommends all elective and non-essential dental services be suspended at once. Treatment for emergencies such as infection, acute pain and trauma can continue.

The CDSBC is asking all registrants to do a pre-treatment risk assessment with each patient, ideally by telephone, before performing any treatment. That assessment will be used to determine if there is any risk to the oral health provider, the patient or the public and if so, the patient will be referred elsewhere or the treatment postponed.

The CDSBC is also cancelling all in-person meetings and non-essential travel for staff.

Health authorities recommend self-isolation for 14 days and monitoring for symptoms such as fever, cough and difficulty breathing.

If you have a COVID-19-related story we should pursue that affects British Columbians, please email us at impact@cbc.ca.