[JulianMorrison]

Detection means there is enough virus physically present in the sample for the detection technology to identify it.

Infection requires virus particles to be physically present in transmission vectors (fluids, droplets, etc). There's generally also a dose-response effect where more particles means more chance of evading the immune system well enough to establish replication in the victim.

So a lack of anything to detect, means a lack of anything to spread an infection.

[_Microft]

> So a lack of anything to detect, means a lack of anything to spread an infection.

One should add that for that the threshold for detection has to be lower than the threshold for infection.

Example: let the detection threshold be 10 particles/ml and the infection threshold be 100 particles/ml (*) -> then undetectable implies that it is very improbable that an infection will take place.

(*) This is a very crude description. Think of it like this: Every single virion (virus particle) has a very low probability of causing an infection itself but there is a high number of them and for one them it might just work out (higher viral load -> higher risk of successful infection)

[hdjjhhvvhga]

> One should add that for that the threshold for detection has to be lower than the threshold for infection.

This statement is logical and makes perfect sense - but it's narrower than the original one.

[Drdrdrq]

Thank you, makes sense!