At the start of last weekend, two negative Covid tests in a row had me thinking that my sore throat was the result of too much conference socializing or maybe a summer cold. But then I self-tested one more time Sunday night, because I was set to fly to Denver the next afternoon for the Stream TV Show–and that positive result has since led to my having to notify more people than I might have imagined.

That list started with the toughest case: my wife and my kid, from whom I’d have to isolate at home until no longer testing positive. Fortunately, in-house quarantine is easier to manage in the spring when you can open every window for maximum ventilation and eat every meal on the front or back porch.

Next I had to e-mail the organizers of my now-foregone conference. I said I’d cancel my flights and keep that trip credit handy for their next event, after which I’d complete my outline for my panel and e-mail those notes to whoever might step in for me. They were okay with that.

Then I e-mailed the people I’d spent the most time talking to at last week’s WithSecure conference in Helsinki. (The organizers had covered my airfare and hotel, but I’m not sure I can call that travel “free” now.) None of them have written back to say that they’ve since tested positive, which makes me wonder if I’d been in the wrong square meter of indoor space for the wrong 15 minutes.

After that, I sent a note to the organizers of Dublin Tech Summit, where I’m supposed to speak next week. I advised them that while I was reasonably optimistic that I’d get past this and resume testing negative by this weekend, I couldn’t guarantee that. They wished me luck.

My last act of notification didn’t invove conversations with actual humans. After getting an official PCR test Monday and receiving the results early Tuesday along with confirmation that they’d been reported to the Virginia Department of Health, I had to share them anonymously with VDH’s COVIDWISE exposure-notification app. That would allow other people with smartphones running Apple and Google’s privacy-optimized Exposure Notifications framework to get warnings of their potential exposure if this software concluded they’d been sufficiently close to me for sufficiently long, as judged by algorithms computing randomized Bluetooth beacons.

The e-mail and text I got from the test operator Curative didn’t say how I would do that. But the app itself explained that I had to visit a VDH page and plug in my last name, birth date and test date to get a verification code that I could then type into the app. That’s “type,” not “copy and paste,” because this Android app refused the latter form of input.

My wife reported that her copy of COVIDWISE pushed a notification of the possible exposure nine hours later. But the more important thing is that no other sort of Covid notification has greeted her or our kid since then. Five days after first testing positive and entering my little house arrest–during which my sore throat and nasal congestion have vanished as the positive strip on my recent tests has begun to look notably lighter than on earlier tests–I remain the only person in the family to have exhibited any symptoms this month or tested positive ever.