I have data like in following table where ESBLProp= ESBL/TBX.

I have two questions:

1. How can I calculate 0/0 for further analysis like regression for proportion? Either remove it or keep it with some transformation.

I don't want to remove it cause exclusion will reduce my denominator so what transformation is perfect to keep it?

2. If I want to take log of proportion then what will be perfect

a. logESBLProp = log(ESBLProp) or

b. logESBL/logTBX= proportion,

each methods have different values.