Hi,
Welcome to HCM.
You had 4th generation HIV COMBO test. It comprises of Two parts. Detecting both P24 antigen and Antibodies for both HIV 1 and 2 infection. But normally antibodies against HIV infection would appear only by 6-8 weeks after the infection and likely to be delayed up to 12 weeks in some individuals. So the negative test done on 6 weeks could be able to rule out HIV 1 infection (P24 antigen for HIV 1 infection) and not the HIV 2 infection. But HIV 1 infection is common (up to 99.5%) world wide except in certain pockets of Africa. So you need not worry. You are almost free from HIV infection to the extent of 99.5%.
Dr S.Murugan

Dear Patient,
Thank you very much for your question. ELISA fourth generation test looks for both HIV antibodies and p-24 antigen,therefore,according to the view of most HIV specialists 6 week period after the actual sexual contact is good enough to give a positive result if infection has occured. ELISA 4th generation test has shortened the window period for HIV because it detects p-24 antigen which appears prior to HIV antibodies and disappears after antibodies are formed. However, according to the WHO diagnostic criteria, you have to wait 12 week period after exposure to confirm you HIV status by antibody testing. Your result after 6 weeks sounds that you are ok but my advice is to wait another 6 weeks and do the same test for reassurance. Also I think you have to meet your doctor and need to treat your anxiety . I have noticed that many young individuals who persistently worry about HIV have anxiety disorders but not HIV infection.
Therefore, consult your physician and treat your anxiety. Also take another HIV test after 6 weeks or 12 weeks after your exposure for reassurance. I hope that I answered your question. If you have more questions, please write me.
Good luck!
Dr. Dinesh Nuwan Weerasinghe. MD.