Welcome to the STD forum. We don't get many questions from people with documented syphilis, although there are many questions from people worried about the possibility.
The direct answer to your primary question is simple and brief: People are almost instantly rendered non-infectious by penicillin. Perhaps within a few hours of the first penicillin injection, and certainly within 24 hours, you could not have transmitted the infection -- even though any open sores or moist lesions of secondary syphilis probably still were present.
Having neurosyphilis during the early stages of the disease is actually fairly common. Dr. Hook and I know know something about it. Just for fun, note the authors of the first modern research study on the subject: http://www.ncbi.nlm.nih.gov/pubmed/3056164 . As you imply, in general early NS is less serious than neurological involvement that occurs in late syphilis. You were trated "by the book"; your infectious diseases specialist obviously knows her business. I'm glad you are doing well. Please be sure you follow the ID doc's advice about follow-up, i.e. stick with the program of follow-up blood tests. But don't worry about the long term outcome. IV penicillin is virtually 100% effective.
Finally, if you don't mind -- can you provide some personal information about your situation? To many questions about syphilis, Dr. Hook and I point out how uncommon the disease is in the US and other industrialized countries, where it generally is limited to a few population groups. In the US those typically are men who have sex with men; non-whites in eastern inner cities (or people who have had sex with such individuals); and Latinos in western border states. For the education of other forum readers, it would be interesting to know where you are and whether and how you link up to those risks or others.
Thanks for posting an interesting question. Good luck to you.
Thanks so much for your quick response and reassurance. I am happy to share some details for your members, though I am afraid that my unusual story may cause unnecessary anxiety among people. I believe that I am a rare case. I am a Caucasian professional woman in an urban Midwestern city. I tested negative for all STD’s in October 2008 and have only had one sexual partner since then. He and I had a long standing sexual relationship, though it was casual and not monogamous. We used condoms for vaginal sex however we did not use protection for oral sex. I believe based on the timing of my symptoms I contracted syphilis in April and when I informed my partner of my diagnosis he admitted he had sex with a woman in the Caribbean while he was vacationing here in March. I believe the woman lives in the Caribbean full time and he believes that is where he contracted it from. He was unaware of his infection though until I informed him. He has since tested positive and was treated as well. I do not remember a sore on his penis or in his mouth but I was intoxicated sometimes when we had sex. I have known this partner for years and have never known him to use IV drugs, have sex with other men or use sex workers. The only thing I can think of that increased his risk is that he contracted it in the Caribbean.
So there is my story. Again, for all the readers out there, I believe I am an unusual case so I hope this doesn’t add to your anxiety. I am going to think twice though in the future about having sex outside a monogamous relationship where we have both been tested. No sex is really safe otherwise.
Thank you for the additional information. Yours is a good story in support of the notion that all sexually active people are at risk of STD, including rare ones like syphilis. Although this scenario indeed is unusual in the US, syphilis is epidemic in parts of the Caribbean, so your story is entirely plausible; I am certain you are correct about the source of your infection.
I'm glad your partner was diagnosed and treated. It probably need not be said, but if he can identify and contact his Carribbean partner, of course she also should be treated.
Best wishes-- HHH, MD
Just read the comments between yourself and LB633 and I just saw that you said not many people with syphilis share information about their experience, and I thought I would share my experience since I JUST got treated for it three days ago.
I am a 26 yo homosexual male, European Caucasian. A couple of months ago I was hit by a wave of flu like symptoms like, headache, fatigue, mild fever, exhaustion, shivers, muscle aches etc. Like most people, I assumed it was just a bug that was going around and thought that a lot of rest, and a few days off work would do the trick, and it did. After that I felt fine and had no more symptoms for a few more days when the same came back again. And again I thought maybe the bug has not yet been killed by my immune system, so I opted for more rest. Then I truly started feeling better and the symptoms went away completely for a couple of months. If you asked me at the time, I would have assumed I was as healthy as a horse and would DEFINITELY not even dream that I was infected with a easily treated but yet dangerous bacteria that causes syphilis. After a period of calm I started feeling discomfort while urinating, and a little tenderness when I tried to masturbate. Very shortly after that (about a week) I started getting a large quarter sized blister on the tip of my penis, that was accompanied by smaller ones.. It was indeed painless like they say, however if I would get a spontaneous erection, the stretching of the sores was indeed extremely painful! And urination was almost impossible, as my urinary tract and tip of penis were swollen shut.. I would have to use a cathador to urinate. Because of finances I was not able to see a doctor right away so I knew I had a month before I could get in for a visit. During the month I researched and assumed it was either herpes or a severe yeast infection, because there was little info on how shyphilis manifests itself, I never assumed it was that. I also started feeling very tired and was unable to focus. It also triggered involuntary "down" moods not simply because of the sores, but I believe the infection affected my mood as well. Once I had the chance to go to a doctor, she asked me a few questions, and the determining factor that it wasn't herpes or a yeast infection before any blood tests were done, was simply the fact that the sores of syphilis haunt you and stay with you for a very long time (1 - 2 months) as opposed to any other infection (1-2 weeks). Once she did a culture and blood test, it was very clear that I was at the end of my first stage of syphilis, and that treatment was needed right away. They also diagnosed me with NGO a bacterial infection of the urinary tract. I was administered two injections of penicillin and a one time oral antibiotic. About an hour after my treatment I felt awful, as if I had the flu again, and I thought it might be an allergic reaction but my doctor advised me that it was a condition called the Jarisch-Herxheimer reaction. When some people with syphilis get treated with penicillin, the "great die off" of the bacteria releases a toxin that makes you temporarily sick, she advised me to wait until the next day and see how i feel, also she said that a hot bath will help, and did it ever!! I started already feeling better after my bath, then the next day was back to normal. It has now been three days and I feel absolutely amazing, the weakness is gone, and my mood is back to normal! And I am officially syphilis negative! :) My experience is mine, and others may go through it in a different way. If you notice anything odd about you, always consult a doctor before making assumptions(like myself) and scaring yourself.
I hope my story helps someone out there who is going through the same thing.