Thanks for the review OP. A very similar thing happened to me once. I thought I should look into what risk I've been taking....
What I discovered is that Herpes is less often passed on from mouth to genitals (type 1 to type 2) although this can and does happen. In reality, most WG are likely to have (either knowingly or unknowingly) herpes type 1, sadly, a great many would be surprised to learn they also have type 2. This is based on the fact that 1-in 6 people have Herpes (a fact in America at least, no large scale British study has been commissioned that I know of). Since a WG will easily see 5/6 guys a day they are likely to come into contact with it on a daily or bi-daily basis, sooner or later they will pick up the oral strain, its inevitable, and it stays in a system perpetually so regular punters will have been exposed to it (type 1) during most punts.
Unfortunately, STI tests for Herpes type 2 are often inconclusive since Its so hard to fully detect unless it is a certain state and lies dormant often for long periods. The regular NHS STD tests offered to WG's are for serious or life threatening viruses only, they do not even test for Herpes. Most people don't know they have it until they experience an outbreak, that can take years sometimes.
She would have known she was carrying the virus if there was an outbreak and it is unacceptable to continue to work in this condition. However, part of me thinks that there is not a WG in the land who would stop working for the best part of a month, even then it does not mean that it can't/won't be passed on - just ain't going to happen.
Only way to avoid catching it from a WG is to avoid oral contact of any sort both ways, no fingering or masturbation either - just sex with Condom. A depressing thought but a harsh reality.
