virion

At that low virion count it’s more about the probability that a virion will attach to the correct CD4 receptor and be able to work inside the cell.

There's not a whole lot of water in a virion, so it shouldn't be torn apart by ice.

It states that each virus particle (virion) has an independent probability of starting the infection in the body.

Not as easily as, say, a bear, but easier than a virion or most regular chemical contaminants.

Technically you could have a full 2 bit adder inside a single virion within a generation.

Those droplets can range from visible (way bigger than a mycobacterium ) to only large enough to hold one virion.

A single read/write of a single virion can be measure as an infection with sufficient pcr cycles (may take 60…).

If you have symptoms it makes sense to wear an N95 if only to reduce the amount of virion you are sharing.

And you have to keep in mind that OP's number does not only include the human virion particles but all virion particles in nature, including megaviruses, virions, virophages, bacteriophages etc.

But no jab ever offered lifelong permanent immunity… every jab ever just offered you some response to that specific virion in the future.

My layman's understanding is that even one virion can potentially infect someone.

Only one virion needs to make it through to initiate an infection.

I understand that he is using "cell" to refer specifically to a single virus particle - a virion.