Expert: John Thai, M.D. - 4/17/2009

Question
QUESTION: Hi,
May i Know how long HIV window periods takes?
and i heard 3 months, if, i tested with any antibody test at 3months, can it be reliable , that i m safe .and should i needed to tested again? i have tested at 12weeks not 3months with antibody test, results was negative.Please advice me, how should i do later..


ANSWER: Hi Jasonshee,

The window period is different from one person to another. There is no standard "window period." The current testing used worldwide is a HIV antibody testing with a confirmatory western blot test if the antibody is positive. The recommended time is 3 months from the date of incident - exposure, sexual intercourse, IV drug use, etc.

In the US, we are currently using other diagnostic methods which can be tested on individuals 2 weeks from the date of incident, such as p24 antigen test and NAAT.

As I am not familiar with your country's testing method, I am assuming they are still using the traditional methods of HIV antibody detection for initial testing.

Should you be negative, then you were not exposed to HIV on that date of the incident. Should you have had any associated risks after the date of the incident, you must get retested.

12 weeks equal 3 months.

Best Regrds,

John Thai, MD


---------- FOLLOW-UP ----------

QUESTION: Hi,
I was tested by BIOLINE (HIV1/2) test, at 3months, after my first or last exposure, so, still i need to worry about or, should i still retest at 6months? please reply me again, so thanks

Answer
There's no need to worry as you were tested negative 3 months after the date of the sexual encounter.

As long as you remained sexually active, it is highly recommended to continue to have a comprehensive STI screening once every 3 months.

Best Regards,

John Thai, MD