There’s an issue of what we care to measure. The number of people who go to the doctor with a rash due to Borrelia bacteria and then take antibiotics and everything is fine might be able to be estimated that way.
On the other hand that’s not really what we care about. We care about not getting long-term problems.
In a similar fashion, if you don’t get Lyme disease but another nasty tickborne disease that can be treated with antibiotics we don’t care that much about the difference to Lyme disease.
There’s an issue of what we care to measure. The number of people who go to the doctor with a rash due to Borrelia bacteria and then take antibiotics and everything is fine might be able to be estimated that way.
On the other hand that’s not really what we care about. We care about not getting long-term problems.
In a similar fashion, if you don’t get Lyme disease but another nasty tickborne disease that can be treated with antibiotics we don’t care that much about the difference to Lyme disease.