How fast for an infected person to become contagious?

I haven’t read this info yet, but suppose Person A infects Person B. How long does it take for Person B to become truly infected (that is, from the moment the virus enters his body, to truly taking up host and propagating,) and how long before Person B becomes infectious to other people in his own right?

12 hours, 36 hours?

Three to fourteen days incubation time.

Source: the Coursera course we took to be contract tracers as need be. (We aren’t doing it but the baseline quantity of people able to was a prerequisite for the state of NY to go to the next reopening phase)

ETA: that’s how long between catching it and developing any symptoms.

There is a TWO DAY WINDOW between the time Person B becomes infectious (which happens FIRST) and the time when Person B gets any SYMPTOMS.

So that would be 1 to 12 days from being infected to being infectious, for those who do go on to develop symptoms?


How long, after the virus takes hold in someone’s body, does a nasal swab test become able to detect it?

also, AHunter3, so this means an infected person becomes contagious very rapidly, within hours, even though asymptomatic?

2-3 days.
Source, that was what I was told when we were representing repatriated citizens, they had to be detained at least 48 hours after arrival and then tested.

This was back in April and one of the Doctors I dealt with told me he didn’t think asymptomatic transmission was a thing and he doubted many were actually truly asymptomatic. I just politely nodded and rolled my eyes then, turns out he was right.

No… sorry, I found it a little confusing myself on 1st take.

Day 1: Person B inhales some virus particles by being too close to Person A

Day 2: nothing

Day 3: probably nothing

Day 4 or Day 14 or anywhere in there: Person B’s incubation period is over and they are now shedding virus particles. Person C can get sick. But Person B has no symptoms yet

Day After That: same shit. Infectious but no symptoms.

Day After That: Person B is likely to be getting headaches and developing a cough

Day After That: Person B is getting sicker, feverish etc. And Still quite infectious, by the way

Day After That: same

Day After That and so on: Eventually Person B’s symptoms are abating. Comes a day without any fever and reduced shortness of breath.

Ten Days After No Fever / No Serious Symptoms: Person B may be assumed to no longer be infectious and can cease being in isolation.