Q and A

Question

What is the difference between 3rd generation and 4th generation HIV test?

You said that the 4th generation test can detect infections earlier but what do the numbers on the test result mean? Does it mean that the person is infected but may need more time for it to show positive?

I had a 4th generation HIV test and the result was 0.06 less than 0.25(cut-off) what does this mean please?

Should the number be 0 if I am really negative?

Answer

Thank you for your question.

The 3rd generation tests look for antibodies (the body’s immune response), 4th generation tests look for both antigens (proteins from the virus itself) as well as antibodies. This means the fourth generation test is more accurate in a shorter time as it does not only rely on the speed at which the body can generate an immune response.

As far as the numbers are concerned. Anything below 0.25 is negative. No-one will get 0. Your result of 0.06 means you do not have HIV. For a full explanation please follow this link to a similar question.

6 comments

  1. Simon Collins

    Hi Rahul

    Answers to questions on transmission and testing are already online at the FAQ page.
    http://i-base.info/qa/factsheets/hiv-transmission-and-testing

    or in this guide:
    http://i-base.info/guides/testing

  2. Rahul

    I had unprotected sex 55 day ago and I have HIV test after 7 weeks of sex when I was having sore throat and report was non-reactive now my question is should I go for another test coz still I have some cough

  3. Roy Trevelion

    Unfortunately we don’t have the resources to answer more questions about transmission and testing. This information service is about HIV treatment for people who are HIV positive.

    We are not doctors, and this is an online service. If you have any kind of rash it’s important that you go to see a doctor so that they can look at it.

    Most questions about testing have been answered here:
    http://i-base.info/qa/factsheets/hiv-transmission-and-testing

  4. cezar

    I might have exposed to the virus on the 29th of April, I did antibodies 3rd generation test on 15th of June 2016, result was negative, noting I started to feel some fever and temperature was 38.2 to 38.5 and small red spots on my stomach with small white heads – this was on the start of june 2016. Now I feel much much better, no more temperature and the spots started to go away, but i still have doubts… I’m 30 years old, male. Please I need your advise.

  5. Charlotte Walker

    Different tests have different cut offs. If your test was negative then you have nothing to worry about.

  6. rohit

    Sir I saw one question saying 0.25 is cut off but in my case the result was said to be 0.35 cut off

    I was negative. I am scared you said 0.25 is cut off. Please explain