Q: How long does HIV take to be tested positive?

A: Thanks for writing in.

My first advice would be to get tested immediately if you believe you have been exposed to risky behavior. Post exposure prophylaxis may be recommended by your doctor. These drugs used to treat HIV are usually taken daily for about 4 weeks to reduce chances of becoming HIV positive.

Having said that, the length of time before a subject tests positive to HIV following exposure (sero-conversion), known as the window period would depend on the type of test done.

An antibody test can read positive from 3 to 12 weeks, if there is sero-conversion. An antibody is a disease-fighting protein produced by the body in response to an infection (HIV infection, in this case).

A combination antibody/antigen test (which detects both antibody and antigen…which is a part of the virus) can read positive from 2 to 6 weeks after exposure, if there is sero-conversion.

A Nucelic Acid Test (NAT) can detect HIV infection in the blood from 7 to 28 days following infection.

Generally, if the initial test is negative, a repeat test is done 3 months after the exposure to ‘close the window’. Some may stretch this to a further screen after 6 months. Be guided by your doctor.

I hope this helps.

Have a good night, everyone J