In many ways, Manitoba and Saskatchewan are mirror images of each other.
They both have Conservative prime ministers. They both love curling and the Canadian Football League. They rank fifth and sixth in terms of population among the provinces – and vice versa in terms of size.
However, in these early days of the COVID-19 pandemic, there is a clear difference between the two provinces neighboring the Prairies.
On Tuesday evening, Manitoba reported 21 confirmed or probable cases of the disease, while Saskatchewan reported 72.
This means that Manitoba has the lowest number of known cases of the disease among all Canadian provinces per capita – while Saskatchewan has an apparent infection rate four times higher.
In general, the two provinces look for the disease in a similar way.
To date, Manitoba has tested 4,520 of its 1.38 million people, which means 0.3% of the population has been sampled.
Saskatchewan has just under 1.2 million people and has tested 5,757, or 0.5% of the population.
The two provinces are also focusing their screening efforts on people with symptoms of COVID-19 who have returned from international travel or who have been exposed to known cases of the disease. Manitoba also tests symptomatic health care workers, First Nations people and patients in intensive care units or personal care homes.
The question is why does Saskatchewan present so many more cases compared to its eastern neighbor.
“It’s a good question, but I don’t have a good answer as to why we are different,” said Dr. Saqib Shahab, Chief Medical Officer of Health for Saskatchewan.
Dr. Brent Roussin, Chief Public Health Officer for the Province of Manitoba, said that he did not know enough about the epidemiology of Saskatchewan to give an informed opinion.
He assumed a possible explanation: Saskatchewan’s neighbor, Alberta, where COVID-19 moves from person to person within the community, rather than jumping from people who have returned from an international trip.
Saskatchewan is “much closer to a province that has shown community transmission,” said Roussin on Tuesday, adding that Saskatchewan is more likely to have imported the disease from Alberta.
Community transmission appears to be the cause of at least four of the 72 cases in Saskatchewan, Shahab confirmed on Tuesday.
“You have to act everywhere in Saskatchewan as if there is an unknown human transmission,” he said.
Steven Lewis, health policy analyst in Saskatoon, said that the confirmed presence of community-based transmission in Saskatchewan means that it is reasonable to expect that the number of cases in Saskatchewan will increase faster in the near future than ‘in Manitoba, where there is no evidence that the virus is spread from person to person at this time.
That doesn’t explain, however, why the Manitoba and Saskatchewan numbers are so different right now, said Lewis.
In fact, the gap between the two provinces is irrelevant at this point in the pandemic, he said.
“The numbers are still low in both provinces and at the start of an epidemic, you will usually see fairly random variations in pockets of epidemics,” said Lewis in a telephone interview in Melbourne, Australia.
“So, it could just mean that [Saskatchewan is] a few days before Manitoba. This may mean that, for one reason or another, people who came for a test in Saskatchewan were slightly more symptomatic than those in Manitoba.
“It may just be a matter of bad luck, in the sense that perhaps a few travelers from elsewhere came to Saskatchewan and were asymptomatic and started to spread a bit and Manitoba did not yet experienced that. “
Lewis said he would be inclined to discern a difference between the two provinces if Saskatchewan had 12,000 cases of COVID-19 compared to 2,000 in Manitoba.
In other words, looking at cases 72 and 21 right now and deciding that there is a difference between the two provinces is a bit like predicting the outcome of an election on the basis of a handful of early warning surveys.
In addition, neither Manitoba nor Saskatchewan have the capacity to randomly sample COVID-19 from their general population, as reported by the World Health Organization.
Manitoba, in particular, is struggling to process COVID-19 because of a shortage of reagents, the chemicals used in two stages of the genetic test for the coronavirus that causes the disease.
A reagent breaks the lipid shell of the virus, allowing access to the genetic material inside. Another reagent efficiently copies genetic material by transforming RNA into DNA.
This is why Manitoba is testing only a handful of categories of suspected COVID-19 carriers. Roussin said he was confident that community transmission was not yet occurring significantly in Manitoba, as few people come to the ER with severe symptoms of COVID-19 – and no one has tested positive in a hospital in Manitoba.
This does not mean, however, that community transmission does not occur in Manitoba. Roussin expects this to happen in the coming weeks.
Without random sampling, there is really no way of knowing how many people are walking around in the two provinces without their knowledge.
“Some epidemiologists have speculated that there could be 10 or 100 times more completely asymptomatic cases. And since we don’t yet have the capacity to perform mass population tests, we really don’t know the prevalence rate, “said Lewis. .
“We know the number of tests we have done, then we know the number of positive tests, but if there are 50,000 people in Manitoba or Saskatchewan who are really carriers of the virus, we do not know that it is the case. But it is not beyond the realm of possibilities. “
This is why the two provinces recommend social distance and warn people to be very careful with their hygiene.
“This is not a reason to panic,” said Shahab of the community broadcast. “It’s a reason to be very attentive to daily activities. You go shopping, you bring your groceries home … you wash your hands.”