The numbers behind Ontario’s warning on safety

It will be another week before we know if Stage 2 restrictions are helping

The world marked the disturbing milestone of 40 million COVID-19 cases Monday, but that’s just the tip of the iceberg according to Colin Furness, an infection control epidemiologist at the University of Toronto.

With estimates that five per cent of the world’s population — almost 400 million people — has been infected to date, “we’re still just getting started,” id Furness. “It’s only a fraction of the total number of COVID cases that must have happened worldwide,” he said. “I mean, if you’re COVID, the feast has just begun.”

Cases are shooting up in areas of Europe such as France, where new confirmed cases numbered 32,000 in one day.

In Ontario, it will be at least another week before we know whether the results of the modified Stage 2 restrictions imposed Oct. 10, which include a ban on indoor dining, are having a positive effect.

“We’d have to look at least two weeks’ worth of data,” said Dr. Lawrence Loh, Peel’s medical officer of health.”

Ontario wide

The seven-day rolling average of new cases in Ontario was 778 on Monday, down from 798 on Friday.

But epidemiologist Ahmed AlJaishi, a PhD candidate in health research methodology at McMaster University, said it will be a week before we know if the modified Stage 2 restrictt ban on

ons, which include a indoor dining in four regions of the province, are having the desired effect.

Al-Jaishi said we should look for lower case numbers in the province in combination with a reduced reproduction number for the virus, which on Monday was 1.05, according to data from biostatistician Ryan Imgrund.

Al-Jaishi says an optimal reproduction number is around 0.8, which means each person with COVID-19 will infect less than one other person, and which will lead to a large decrease in the number of cases over time, he said.

Confusing things is a higher positivity rate, which refers to the proportion of tests that are coming back positive.

According to Public Health Ontario, 3.1 per cent of tests were positive on Oct. 19, which was 0.6 percentage points higher than the day before.

Al-Jaishi says the increase in positive tests is “pretty significant,” but he thinks the growth is due to a policy change by the government, which is now only testing symptomatic individuals at assessment centres, and not due to a higher prevalence of the disease in the population.

Hot zones

Ontario’s chief medical officer, Dr. David Williams, advised against trick-or-treating in four areas under modified Stage 2 restrictions, which include Peel, York, Toronto and Ottawa.

Medical officers of health for each region agreed. The four areas accounted for nearly 70 per cent of the province’s 794 cases reported Monday.

“We do know that if it was perfectly done, in an ideal setting, we know that you could reduce the risk significantly, especially if people stayed apart,” said Loh. “But we also know that in the real world, it’s not always perfectly done.”

Peel Region has logged more than 100 cases a day for the last two weeks.

Loh said the high numbers are driven by a “significant data drop from the backlog of tests” in the province last week, as well as a “triad” of transmission among people getting the virus at work or a social gathering transmitting it to houseand hold members.

York Region is also battling a spike in cases.

“York Region Public Health has recorded a sizable increase in the total number of COVID-19 cases over the last month,” said Patrick Casey, director of corporate communications for York Region in an email.

“Our seven-day average as of Oct. 18 was 71 cases. For comparison, a month ago, Sept. 16, our seven-day average was 21.6 cases and on Aug. 16, our sevenday average was 3.6 cases.”

Casey said that a large proportion of cases have been in people younger than 40.

Toronto had 268 new cases on Monday, and added two neighbourhood maps to its online dashboard showing rates of testing, as well as per cent positivity.

Ottawa’s medical officer of health, Dr. Vera Etches, also encouraged residents to find alternatives to the traditional trick-or-treating.

Europe on fire

After appearing to get a handle on the spread of COVID-19 in the summer, Western Europe is once again experiencing surges of the virus.

Health authorities are now scrambling to enact restrictions to halt the spread.

Despite the enactment of new rules, countries such as Germany, France, Italy and Poland

kes, as cases in the continent sit around seven million, with close to 250,000 deaths.

Spain leads the way with the most overall cases, at 936,560, according to the European Centre for Disease Prevention and Control, followed by France (897,034), the United Kingdom (722,409) and Italy (414,241).

Furness said he believes the a current surge in cases was unca European Union began to promote and allow tourism and travel over the summer.