The member raises a really good question.
In fact, I think that exact risk that's identified by the minister really informed the policy that has developed in two ways. The first is on the test the member is referring to, the post-arrival test. The core issue here is that in the first few days the virus is in the body, it's possible that it won't show up in even a PCR test. It takes a few days and then it starts to show up, but that post-arrival test, where the person has to stay in the airport hotel until it clears negative, is not the first test. It's the second test. They've already had a test up to 72 hours before they actually departed.
That test, depending on the exact details, is probably happening two, three or four days after the first test, so they're not clear of just one test; they're clear of two tests. The risk of their having COVID is much less than the statistics implied by the McMaster study. Also, then, they're still under an obligation to follow strict protocols for travel, and they're still under an obligation to follow a strict quarantine in, say, their homes. Then there's a third test at the end of that.
Building a system with three tests in it is geared to actually eliminate, to the greatest extent possible, the risk of anybody slipping through, because at any one point in time you may show a negative test even though you do have COVID. After those three tests, I think there's a high level of certainty that the person is clear of COVID and safe to move about their daily life.