For contagious viruses?
Has there ever been a study that proves person-to-person transmission of viruses?
In the entire history of the published medical research, there is not one so-called pathogenic disease-causing virus that has ever been found in one bodily fluid of one person. Not HIV, Ebola, Zika and SARS-CoV-2. Do you disagree with that? Present a paper proving such and explain the process fully. You’d be the first in all of mankind to do so.
Source : https://stolenhistory.net/threads/viruses-are-not-contagious.5618/
Chicken pox is probably the best Steel Man argument to consider. it does indeed seem contagious
Take a look at this claim :
Source : https://www.westonaprice.org/sv/podcast/covid-there-is-no-virus/