Hello, doctor. I'm a gay man live in China.I had sex with another boy yesterday. Before the incident, I tested him with an HIV test paper, and he told me that his last test result was negative, but I was not at ease. The instruction manual tells me that I only need to drop 1-2 drops of dilution, but I may drop a little more, about 3-4 drops in total. His test result is negative. Then he squeezed the lubricant into my anus, and then put his fingers in to expand it. I don't know which fingers he used. I'm afraid of the finger he just got stabbed by the blood collection needle. Later, his penis was inserted into my anus with a condom, but this was my first anal sex. I felt too painful, so he entered within two minutes and I asked him to withdraw. Finally, we masturbated each other and ejaculated. I was scared after that. I don't know whether I should use PEP or not. My local CDC doctor told me that I don't need it. He thinks it's safe sex, but I'm very anxious and want to hear your opinion. Thank you!

Welcome to the Forum.  Thanks for your questions and your careful description of the events which took place.  I agree with your doctor- you have every reason to feel comfortable that the encounter you describe was safe sex.  I see no reason for PEP of concern.  Your partner said he did not have HIV and you verified this by testing him.  Then your sex was condom protected.  Even if he used the finger which had just been stuck for testing to insert into your rectum, there would be no risk for that.  Mutual masturbation, even if your partner's genital secretions got on you would also be no risk.  I would not worry.  Congratulations on your practice of safe sex.  EWH---

Thank you, Dr. Hook. I'm just confused. My doctor told me that when using the HIV test paper, it's best to drop 1-2 drops of diluent, but I told him that I might drop 1 more. He said it didn't have much effect on the result, but he didn't tell me why? Do you agree? 

I agree that one extra drop of diluent is unlikely to change the result of the test.---

Thank you, Dr. Hook. I think I should be fine. I always think about the situation too extremely and always want to get a 100% sure answer, but nothing is 100%. The last question, if I use the fourth-generation self-test kits, how many days can I test at the earliest? Thank you again.

Final answers---