Coronavirus aka COVID-19 aka SARS-CoV-2 viral particles and infections

No.11496798 ViewReplyOriginalReport
I've been searching and searching but can't seem to find an answer that's been bugging me for a day. How many of these fuckers do you have to inhale or have enter your bloodstream before you become sick?
Does getting exposed to even a single particle fuck you up?
Has any lab done studies on this or maybe studies on Influenza particles?
Is there a name for this type of research?