CR: Not understanding passage

[AceTheGM@]

Sometimes I struggle with understanding the situation described in a CR question. Specifically, I just attempted Verbal2 CR #62, and have no idea what's going on in the intro paragraph. I've tried reading it slowly and mapping out what's going on, but I'm still stuck. Here's as far as I got:

Antib--> destroy virus
H infection-->kert in eye
eye cell = H cell

I am so confused by the last statement of the passage. I thought keratitis was caused by the herpesvirus, not by antibodies to it?

More broadly, I need help with a general solution for when I don't understand the upfront situation in a CR question.This happens from time to time. What's the best way to approach a problem / guess when I get "stuck" like this?

[RonPurewal]

Please re-post this question in the general verbal folder. Thanks.