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It is contagious. Some people don't show symptoms and can therefore pass it on without knowing they even have it. I was engaged to a guy for a year before he gave it to me. We did not marry. He did not tell me in advance that he had it, and I felt cheated. There is no cure. Always have protected sex with condoms and then wash thoroughly with soap and hot water afterwards and there will be a good chance you will not pass it on. You can get recurrences as seldom as once every 2 years or monthly. Sounds like you have a good immune system and a very mild case. Flareups will likely last about 1 week. You will get to know the signs that its coming, some itching and aching and you are "active" during this time and can pass it on to your partner. When your sores are open and for a few days after they heal, you can pass it on. You must be very careful not to pass it on. But rest assured, if you do your research you will find about 25% of the adult population has it -- alot of people not practicing safe sex. Good luck to you.