TORONTO — Ontario has reported the deaths of more than 1,000 people due to COVID-19 so far this month, a grim figure the province's top doctor largely attributes to the previous, more virulent strain of the virus, though he admits the data is murky.
The province has logged persistently high numbers of fatalities each day this month, despite the dominant Omicron variant of the virus typically causing milder illness and all but replacing the more severe Delta variant almost six weeks ago, while circulating among a well-vaccinated population.
Chief Medical Officer of Health Dr. Kieran Moore said officials are trying to ascertain what factors are causing so many Ontarians to die, including whether Delta or Omicron or a combination of the two is responsible, but whole genome sequencing to determine variant type takes weeks.
Essentially 100 per cent of outbreaks in the community are Omicron right now, Moore said, but roughly 10 per cent of hospital admissions are still "relevant to Delta."
"Death is a delayed signal from an outbreak, given that we've got access to health care and an ability to try to protect people through hospitalization and intensive care unit settings," he said this week.
"In the first several weeks of January, we're confident that a significant proportion of (the deaths) were from Delta."
Dr. Andrew Morris, an infectious diseases doctor, said many deaths are likely the result of infections that occurred as far back as early December, when Delta was dominant.
"We know that deaths are a lagging indicator, that they're often reported substantially later than they occur," he said.
"But even if they were mostly due to Omicron, it wouldn't surprise me just by the sheer volume of cases that we've seen, along with the fact that many of the very sick patients that we've been taking care of are either unvaccinated or under vaccinated and (their illnesses) behave very much like some of the earliest cases that we saw with COVID."
According to data from Public Health Ontario, there have been 1,075 deaths related to COVID-19 reported so far this month. About 57 per cent of the people who died were aged 80 or older, and another 35 per cent were people between the ages of 60 and 79.
The vaccination status of the people who died is not readily available, but Public Health Ontario says that in the past month, unvaccinated people aged 60 or older were more than 22 times more likely to be hospitalized due to COVID-19 than their peers who received booster shots.
Dr. Sumon Chakrabarti, an infectious diseases doctor, said Omicron is causing disease differently than COVID-19 has in the past, and that may be a factor in the higher numbers of deaths.
During the third and fourth waves, there was a lot of "classic COVID," a severe pneumonia requiring lots of oxygen, Chakrabarti said. It could be treated, but some would go on to require ICU care and some would die. Many of the people who died were unvaccinated, and many were younger, he said.
With Omicron, a lot of people are being admitted to hospital for reasons other than pneumonia, with COVID-19 triggering other issues or exacerbating existing conditions, particularly in older people, Chakrabarti said.
"They're not coming with classic COVID requiring lots of oxygen. COVID is a thing that causes a mild fever, mild illness, but that's enough to put a lot of these individuals over the edge," he said.
"It's disproportionately causing destabilization of medically fragile individuals, who tend to be older, and their risk of dying to begin with is higher. But that's not to say that there isn't unvaccinated people coming in with classic COVID and dying. That's happening, but it's just this extra, new kind of feature that we didn't see in previous waves is really coming to the forefront right now."
Moore said he is trying to refine the death reporting process to make clearer if each fatality is caused by or associated with COVID-19. Ontario is also planning on doing a "selective review" of death certificates and documented deaths to assess the quality of the data.
As well, Moore said, he will be looking at "all cause mortality" to see if the province's reporting structure is missing deaths that could be associated with COVID-19.
"It's very important that we have good data for all Ontarians to understand the impact of COVID-19," he said. "It won't be changed in a day. It's going to be a journey to improve that level of data."
This report by The Canadian Press was first published Jan. 28, 2022.
Allison Jones, The Canadian Press