The weekly briefing folds seven days of samples into one number. Daily Watch gives you every sample on the day it was taken, site by site. We check PHAC every minute, so the moment new samples post, they are in your inbox.
Every flush in the catchment reaches the plant. One sample reads a whole city.
Sites sample two to five days a week. Daily Watch keeps every one, dated to the day.
Labs test each sample for the virus, and PHAC posts the results in batches.
We check PHAC every minute. New samples reach your inbox within minutes.
| Site | Past year | Sampled | vs a week earlier |
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Have COVID rapid tests (RATs), N95s, surgical masks or gloves you won't use? Tell us what you have and where you are. We get them to people who need them, starting where the wastewater signal is highest, and we email you to arrange the handoff.
The numbers above reward a little context. Adam runs the debrief; Kirk asks the questions a normal person actually has; Spock answers them. Read along, or press play and let it scroll.
People infected with SARS-CoV-2 shed the virus's genetic material in their stool — often before symptoms, and whether or not they ever get tested. A treatment plant pools the waste of a whole city, so one sample is effectively a census of tens of thousands of people who never volunteered for one. Surveillance you can't opt out of, working in the public's favour.
That value on the line is a normalized viral signal — a concentration corrected for how dilute the sewage is. It is not a case count, and it is not comparable between sites in absolute terms: plumbing, population and lab method all differ. The honest question is never "how high," but "rising or falling, here, versus last week." Read every line against itself.
Three years in, a rhythm is unmistakable: peaks around each December–January, troughs by late spring. It isn't clean seasonality — new variants drove off-season bumps — but each winter's height has trended below the chaos of 2023 and early 2024. As of the latest week, the national signal sits near the floor of the whole series, single digits, and still declining.
Down at the manhole, many sites read "non-detect" or "no recent data." Those mean different things: non-detect is real — the signal genuinely fell below the limit of detection this spring; no recent data just means a site reports less often, or paused. Absence of a number is not absence of virus. Across every reporting province the picture is low and steady to decreasing; no region is climbing.
The same samples are screened for influenza A and B and RSV — one pipe, a multiplex panel, a near-complete read of the respiratory season. While COVID sits at the floor, flu A is low and falling, flu B is moderate, and RSV is moderate but decreasing. The whole respiratory season is winding down together: exactly the seasonal exit you'd expect.
Use it as a weather forecast, not a diagnosis. When your region's line turns up for two or three straight weeks, that's your early warning — mask in crowds, test before visiting someone fragile, time a booster. When it's at the floor, as now, ease off, informed rather than guessing. It leads clinical signals by roughly a week, and that week is the entire point.