I don't know the exact numbers. I know there's a very low percentage of cases of drug-resistant TB in Canada. There are only a handful. However, as I mentioned, given the expense and complexity of treating TB, even a couple of cases—25 cases a year—is an incredible pressure on the health care system. As I mentioned, people being in treatment for two years, being hospitalized, often needing to be brought to specialized centres and therefore being away from families and economic opportunities, is really a great burden. The number I mentioned—of an extensively drug-resistant patient possibly costing up to a million Canadian dollars for treatment—is obviously a massive issue.
In addition to the public health issue, the infectious nature of the disease makes the patient not just an issue for the health care system, but also raises concerns regarding the confinement of that patient, avoiding further outbreaks, and finding potential family members and community members who may have been infected through that patient in the time before they were diagnosed.
It's a relatively small problem, but it's already at the point where even a handful of cases becomes seriously problematic.