The Middlesex-London Health Unit is still awaiting final data but says the likelihood of an Omicron cluster associated with at least 30 COVID-19 cases is “very high.”
The cluster of cases is linked to travellers who arrived in London, Ont., from Nigeria in late November.
Acting medical officer of health Dr. Alex Summers said many of the individuals associated with the cluster were fully vaccinated, including the travellers, who had also followed Public Health Agency of Canada guidelines around testing.
The health unit announced Monday that it received word Sunday night that two of the 30 cases screened positive for S gene target failure, which is a marker for the Omicron variant.
The cluster is linked to several schools and child-care centres. The health unit was still in the process of notifying those communities on Monday and, as a result, was not yet publicly identifying them.
“We didn’t want to notify the general public before individuals in that community were notified,” Summers said.
The cluster is also linked to an outbreak at God’s Favourite House, a church on Dearness Drive.
“The number of high-risk close contacts continues to increase and is expected to exceed 100,” the health unit said in a statement.
“All positive COVID-19 cases and high-risk contacts associated with this cluster are considered to be persons under investigation (PUI) for Omicron.”
Summers said, so far, symptoms reported by those associated with the possible Omicron cluster have been consistent with what’s been seen with other COVID-19 strains to date, including respiratory symptoms and a loss of sense of smell. There are currently no known hospitalizations associated with the cluster.
When it comes to new variants, Summers said there are three questions that experts are trying to answer: Is it more transmissible or infectious? Does it cause more severe illness? Do our vaccines still work?
With Omicron, Summers said it does appear to be more infectious or transmissible than other variants.
It’s unclear whether it causes more severe illness but “early indications suggest it does not cause more severe illness.”
“Don’t know if it causes more mild (illness), however, we are monitoring that closely. We do not have enough information here locally to have any comment on that.”
It’s also unclear the extent to which vaccines are effective against the variant, though Summers said experts believe that the vaccine, even in the worst-case scenario, will still be somewhat effective.
With a climbing case count even outside of the possible Omicron cluster, Summers said the health unit would be issuing additional guidance later this week, likely in the form of “strong recommendations.”
He noted that locally much of the transmission is in unregulated environments.
“Social, after-hour environments,” Summers explained.
“The most effective mechanism for us is to make strong recommendations around our behaviours in those settings.”