totally agree, also I’m sure length of contact and what part of...

totally agree, also I’m sure length of contact and what part of the body you contact with makes a difference. And 1 in 10000 causes “infection”. Colonisation/contamination and infection are different things. In general the probability of infection is usually very low, especially in healthy individuals. It’s more probable to have a fungal ball of aspergillus colonising your lung than to have an aspergillosis infection...

if every contact results in contamination; then you contaminate other surfaces; pretty soon all surfaces are contaminated.
really 1 in 10000 is very high. Only a matter of time before you get infected.