The number of germs isn't a useful measure. A credit card is probably full of your own germs, while cash comes to you with a representative sample of other peop

The number of germs isn't a useful measure. A credit card is probably full of your own germs, while cash comes to you with a representative sample of other peoples' microbiota. A screen could be effectively wiped even for every single customer, or you could wash/disinfect that one fingertip, or use one of the strawberries you are paying for (remember not to eat it).