Dr. Tan and Partners is one of the few approved Anonymous HIV Testing Centres in Singapore. A detailed write up on our service is available here.

Other STD services: Early STD Screening, Rapid Hepatitis B Blood Test, Swab for Gonorrhea and many more... contact us to make an appointment now!

HIV 4th Generation Test Singapore

The HIV 4th Generation Test is one of the most accurate and fastest way to determine is a person has been infected with HIV or not.

The HIV 4th Generation Test is also called the Combo test or the Duo test.

It tests for both the HIV antibodies as well as the antigens in the blood. It can be done as a rapid test i.e. you can get the results in 20 minutes.

Antibodies are produced by the body when it is infected with the HIV virus. There are many different types of antibodies. The one that is produced the earliest is called the IgM antibody. This can be produced as early as 20 days post exposure. 3rd and 4th Generation HIV tests can detect the IgM antibody.

Antigens are bits of the HIV virus shell that can be found in the blood as early as 14 days post exposure. The 4th Generation test can detect the presence of this antigen.

If the test detects either the presence of HIV antibodies or antigens, it means the patient is most likely infected with HIV. This has to be confirmed with another ELISA test. We always do at least 2 tests before diagnosing a person as HIV +ve.

Officially it is conclusive at 28 days post exposure. However, from current scientific data, we know that when the test is done at 20 days post exposure, it is already as good as 100% accurate. Personally I have tested patients +ve for HIV at only 14 days post exposure with this test.

The US CDC recommends the HIV 4th Generation test for all HIV screening. This is because it is more accurate, has a shorter window period and can pick up rare cases of sero-negative infections (see below).

The HIV 4th Generation test can detect HIV infections in very rare cases of people who are infected with HIV but never produce any anti-bodies. These are called sero-negative infections and happen in about 1 in 1 million people.

At our clinics the HIV 4th Generation test costs $150 (before GST).

You can walk in our clinics at Robertson Walk, Bencoolen Street, Novena Medical Center or Scotts Road anytime during our opening hours for this test. It only requires a finger-prick of blood and 20 minutes to get results.


We are Open on Saturdays and Sundays.

Click Here for Contact Details, Address and Opening Times.

Feel free to email your queries, feedback and suggestions on what other topics you want to see in the comments section below.


Click here for HIV Testing FAQ

More on HIV symptoms.

If you have any questions, visit our free online forum on sexual health, HIV and STDs.

Click here for Info on STD Symptoms in Men
Click here for Info on STD Symptoms in Women
Click here to see the full range of our HIV/STD Services

If you need a HIV test visit Our Clinics anytime during our opening hours. You do not need an appointment.


Find out more about Anonymous HIV testing at our clinics.

Can’t wait for 3 months to find out? Find out more about Anonymous Rapid HIV Combo test at our clinics.

If you had a high risk exposure to HIV within the past 72 hours, you can take medicines to reduce your risk of actually contracting HIV. Find out more on HIV PEP Treatment.


Related Topics:

Anonymous HIV testing at our Clinics

HIV – Understanding the Window Period

Cost of HIV/STD tests at our Clinics

Condom Broke

Getting HIV from Oral Sex

More on HIV symptoms

How long can HIV live outside the body?




Need more advice?

Come down to Our Clinics for a discussion with Our Doctors, or call our clinics for more information:

1.) Robertson Walk (Anonymous HIV Clinic)  (+65 6238 7810)

2.) Bencoolen Street (+65 6884 4119)

3.) Novena Medical Centre (+65 6397 2095)

4.) Scotts Medical Centre (+65 6694 2348)

5.) Somerset – Orchard Building (+65 6262 0762)

6.) Katong – East Coast Road (+65 6635 2551)


Where to find us – here

Selected clinics are open on Saturday and Sunday.


Email: [email protected]


All Our Doctors are Fully Certified and Trained to conduct specialised HIV Testing.


For lady patients who prefer female doctors, we have professional certified female Doctors to attend to your medical needs.

About Dr. Tan
Dr. Tan graduated from the National University of Singapore in 2001. His residency was in the two largest public hospitals in Singapore; Tan Tock Seng Hospital and Singapore General Hospital.

Find the profiles of our panel of doctors.


  1. prathap

    Hi sir ….

    Morning, firstly this forum is proving to be a big help at this time to me. Just a question to throw out there to everybody. have read on here that transmission of HIV is very difficult from female to male vaginal sex -iit is true.

    1)Iam unprotected vaginal sex single exposer hiv positive girl.iam circumcised male.male circumcised reduce the risk it is true.
    2)15 months post exposer my hiv westren blot ,hiv rna pcr qualitative ,4th generation test ,elisa,tridot all are negative.
    3)what is the exact hiv windowperiod.
    5)some doctors says every 6 months take hiv test hiv windowperiod is 3 months to 10 years it is true.
    6) iam take every 6 months hiv test ar any further test is nedded.
    7)iam worried this reason about my partner hiv positive but my test result all are negative any delay seroconversion iam become positive.
    8)iam thinking all.ways my partner hiv positive but still iam negative but future said it is come positive.no sleeep..,no eat……only think hiv………… pls clarify me
    thank you for your great job…..

    Delay seroconversion My result is change in future….

  2. Hello doctor!

    I had unprotected vaginal sex for less than 20 seconds, afterwards I’ve put on condom to finish off the sex on Jan.

    30 days (4 weeks) after the intercourse, I did 3rd Gen – Test was NEGATIVE.

    50 days (7 weeks) after the intercourse, I did 4th Gen duo – Test was NEGATIVE.

    Do you consider my test as conclusive? I was told that it is 99.99% accurate for the 4th Gen test on the 50th day….

    • Dr. Julian Ng


      Generally, your test result with the 4th Generation HIV test on day 50 post-exposure is conclusive.

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