'Big uptick' in Ottawa's coronavirus wastewater levels in recent days
Public health recommendations still to mask, vaccinate and stay home when sick
Levels of coronavirus in Ottawa's wastewater are comparable to last January when the Omicron subvariant was at its first peak, some experts say.
"We're seeing a big uptick," said Tyson Graber, associate scientist at the CHEO Research Institute and co-lead investigator on the COVID-19 wastewater project in Ottawa.
According to the data, the SARS COV-2 signal in Ottawa's wastewater roughly doubled between the third and fourth weeks of December, Graber said.
While Graber said the new XBB.1.5 COVID-19 subvariant likely isn't in the nation's capital in large quantities, it does remain a cause for concern.
But what's likely driving the high levels, according to preliminary data, is the BQ.1.1 subvariant that appears to have entered Ottawa in November and spread through holiday celebrations, Graber said.
But while BQ.1.1 may be responsible for what brought us here, some experts believe XBB.1.5 — a mutated version of Omicron — could "outcompete" other subvariants with its already rapid rise in the U.S.
The situation in Canada is more murky, given delays in data collection from across the provinces over the holidays, but Graber's team expects to see more of XBB.1.5 in the coming weeks.
"We do have some clinical sequences with XBB, and particularly XBB.1.5, in Ontario," he said. "So it is indeed here. It's just a matter of how fast that grows — and we don't know yet."
Graber also said people shouldn't panic, adding it's just the latest subvariant trying to find its niche.
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In an email, Ottawa Public Health said its recommendations for what people should do to protect themselves and others don't change for any particular variant or subvariant of the virus.
Those recommendations include wearing a mask in indoor settings, having up-to-date vaccines — including a flu shot — screening oneself for even mild symptoms and staying home when necessary.
It said in its weekly Wednesday update coronavirus and other respiratory virus activity in the city was rising, while flu activity was stable after two weeks of dropping.
Difficult to know what's in store
Dr. Doug Manuel, a physician and senior scientist at The Ottawa Hospital and a professor at the University of Ottawa, said COVID-19 is on the rise in the northern hemisphere, with the nearby northeastern U.S. being one hotspot.
Manuel said new variants like XBB.1.5 are coming to Ottawa, but many questions remain.
"The question is, how much is this going to get into our vulnerable populations, our long-term care homes, our older folks, and result in a lot of morbidity and hospitalizations?" he said.
While it may be more transmissible, XBB.1.5 isn't believed to be more severe, Manuel said.
"We don't know yet. We don't think so," Manuel said. "But, again, worldwide, it's difficult to get this information quickly."
Graber said it's difficult to forecast what the presence of variants paired with already high levels of the virus in wastewater means for Ottawa.
"It's pretty safe to say at this point, we are in another wave. What is extremely difficult to predict is how high we will go," he said.
"My prediction right now is that this won't be a large wave, but I'm really not going to hang my hat on this. Because we've been wrong in the past and will be wrong again."
With files from CBC Ottawa News at 6 and Kim Drummond