VANCOUVER -- British Columbia has now identified 18 cases of the U.K. and South African coronavirus variants, including seven that were confirmed over the weekend.

Provincial health officer Dr. Bonnie Henry said the latest seven cases all involve the U.K. variant known as B.1.1.7, which is believed to spread more easily.

The province has now recorded a total of 14 cases of the U.K. variant and four of the South African variant B.1351, which shares some of the same mutations.

While all of the U.K. variant cases have involved travellers who recently returned to Canada and their direct contacts, health officials are still "actively trying to determine" where the four South African variants came from, Henry said.

On Sunday, families in one Metro Vancouver community were sent a letter alerting them about a potential exposure to one of the more contagious variants on school grounds.

According to officials, someone tested positive for COVID-19 after being inside Garibaldi Secondary in Maple Ridge, and that person is also a close contact of a confirmed variant case.

It's unclear if the individual is a student or teacher.

Given concerns about the transmissibility of the new variants, Fraser Health said it's working to "identify any further connected variant cases to ensure immediate isolation and case management."

"The variant strain can transmit more quickly and easily but does not seem to cause more severe illness, nor interfere with the effectiveness of vaccines, nor affect our ability to test for the virus," the health authority added in a statement.

At her virus briefing on Monday, Dr. Henry said health officials have ordered testing on everyone in the individual's school cohort.

Last week, health officials in Ontario shared new modelling that suggests the U.K. variant will likely be the dominant strain in the province by March – a troubling forecast that could force the government to reassess its approach to containing the spread.

"The new variants give us less room to relax and less room for error," Dr. Adalsteinn Brown, co-chair of the province's COVID-19 science table, said on Thursday.

The modelling still indicated Ontario's current downward trend in cases could continue if it maintains its public health measures.

British Columbia has not made any such predictions. Health officials in the province are expected to share updated modelling information on Friday.

For now, Henry said health teams are searching for variant cases through random sampling in areas where COVID-19 infections are increasing, targeted testing of specific demographics, and testing of every confirmed case involving a traveller who arrived in B.C. from an international destination.