Ive had it twice.
As far as the ratio numbers I do not know. I do know that the first time I had it I for about 9 months before it was discovered, and mind you I had no symptoms, none. It had turned into Neurosyphillis which was an absolute night mare. It was treated with a hospital stay and 4 weeks of pic line antibiotics. The second time, also, no symptoms. Went to my HIV Dr with a sore throat and she immediately did a syph test which came back positive, that was treated with 2 weeks of oral antibiotics. Its a mysterious disease in the sense that it can mask as many different things and go undetected, and if it goes undetected I can kill you. I agree that everyone who is sexually active should get three month screenings. As far as mu advice to you, Id go to an STD clinic that specializes in STD's and explain the situation and go from there. Sadly this shit aint no joke.
