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Understanding HIV

Understanding HIV




HIV (human immunodeficiency virus) is a virus that attacks the body’s immune system, making a person more vulnerable to infection and diseases. It is spread through contact with certain bodily fluids from a person with HIV. Most people get HIV through sex without using a condom or without taking medicine to prevent or treat HIV. Other common route of transmission includes sharing injection drug equipment, such as needles. If left untreated, HIV can lead to AIDS (acquired immunodeficiency syndrome).



AIDS (acquired immunodeficiency syndrome) is a late or advanced stage of HIV infection that occurs when the body's immune system is badly damaged because of the HIV virus. A person receives an AIDS diagnosis when:

  • Their CD4 cell count falls below 200 cells per cubic millimetre of blood (or 200 cells/mm3) (A healthy CD4 count is above 500 cells/mm3); or

  • They develop one or more opportunistic infections regardless of their CD4 count.

To learn more about HIV, please visit:

Getting tested for HIV is the only way to know your HIV status. Knowing your status is important to keep you and your partner healthy. Delay in detection and diagnosis leads to late initiation of treatment with poorer prognosis and outcomes, increasing the risk of onward transmission of HIV infection. To find out how often you should be tested for HIV, click here.

In Singapore, HIV testing is traditionally performed in hospitals, clinics and through services provided by community-based organisations. Some clinics provide the options of rapid testing with results delivered in 20 minutes, or anonymous testing services. In 2008, the Ministry of Health (MOH) also implemented a voluntary opt-out screening (VOS) programme for all adult inpatients in public restructured hospitals to improve detection rates and reduce the prevalence of undiagnosed and late-stage diagnosis HIV infection.

HIV self-test kits can be purchased under the HIV self-testing pilot programme at the Department of Sexually Transmitted Infections Control (DSC) Clinic and Action for AIDS (AfA) Anonymous Test Site (ATS) at 31 Kelantan Lane.

Understanding HIV Test Results

You tested HIV negative, what's next?

A negative result means that no signs of a HIV infection were found in the sample. But that does not mean you do not have HIV, because of the window period (the time between HIV exposure and when a test can give reliable results).

Different HIV tests have different window periods. Ask your healthcare provider about the window period for the HIV test you are taking. For HIV self-test kits, you can find the information in the package.

In general, if you have a negative HIV test result and the last possible HIV exposure was:

  • Less than 72 hours ago, you may need post-exposure prophylaxis (PEP) (see PEP below under 'HIV Prevention and Treatment').

  • Less than 90 days ago, you will need to repeat the HIV test again to be sure.

If you have a negative test result again after the window period, and have no possible HIV exposure during the time, then you do not have HIV.

Now that you know you are negative, it is important to stay HIV negative and protect your health.

Tips to stay HIV negative:

  1. Practice the ABCD approach to prevent HIV (Abstinence from casual sex; Be faithful; Correct and consistent condom usage; and early Detection)

  2. Consider taking pre-exposure prophylaxis (PrEP) if ongoing risk (see PrEP below under 'HIV Prevention and Treatment').

  3. Test regularly for HIV, or every 3-6 months if engaging at risk behaviours

You tested HIV positive, what's next?

All positive test results require a follow-up test for confirmation.

  • If you test positive on a HIV self-test kit, repeat the testing at a healthcare facility (including anonymous testing sites).

  • If you test positive in a healthcare facility, this will be done automatically.

If you have a positive test result again, it means you have HIV.

What to do when diagnosed with HIV?

There is currently no effective cure for HIV, but it can be controlled with proper care. By taking HIV medicine (called antiretroviral therapy or ART), people with HIV can live long, healthy lives and protect their partners. With early and effective treatment, people living with HIV can lead lives no different from others.

HIV treatment is available in most public (NCID, National University Hospital , Singapore General Hospital and Changi General Hospital) and private healthcare institutions in Singapore.  Most commonly-used HIV medications are subsidised, making them accessible and affordable.

To learn about the HIV patient journey at NCID, click here.  


Pre-exposure Prophylaxis (PrEP)

Pre-exposure Prophylaxis (PrEP) is a risk-reduction treatment against HIV, which involves the use of HIV medicine for people who do not have HIV but are at risk of HIV infection. When taken as prescribed, PrEP is highly effective at preventing HIV infection. As PrEP only protects against HIV, condom use is still important to prevent other sexually transmitted infections (STIs).

To find out if PrEP is suitable for you, click here. Talk to your doctor if you are interested in PrEP.

  • For more information regarding PrEP services in NCID, click here. PrEP services are also available at other public and private healthcare institutions in Singapore.

  • For any other PrEP related enquiries, call the NCID HIV PrEP clinic at (65) 6357 7000 or email


Post-exposure Prophylaxis (PEP)

Post-exposure prophylaxis (PEP) is a short course of HIV medicine to prevent HIV after a recent high-risk exposure to HIV. PEP should be used only in emergency situations and must be started within 72 hours after a possible exposure to HIV.

A high-risk exposure to HIV includes:

  • Any unprotected anal or vaginal sex with a partner who is HIV positive or a person in a HIV-risk group (commercial sex workers, IV drug users, men who have sex with men/ bisexual men),

  • Sharing of or exposure to contaminated needles or blades, particularly needle-stick injuries, or

  • Victims of sexual assault

PEP is not a substitute for other HIV prevention methods such as consistent condom use, and it is not meant for regular use by people who may be exposed to HIV frequently. One should consider PrEP instead if there is repeated exposure to HIV (see PrEP above). Talk to your doctor if you think you need PEP. 

Should you require PEP after operating hours, over the weekends and/or during the public holidays, please visit the Emergency Department of any public hospital and request for PEP.


Antiretroviral Therapy (ART)

Antiretroviral Therapy (ART) is recommended for all people who are infected with HIV. Although ART cannot cure HIV, it can control the virus and help people with HIV live longer, healthier lives. ART can also reduce the risk of HIV transmission (refer to Treatment as Prevention below); however, it does not prevent transmission of other STIs.


Treatment as Prevention (TasP)

Treatment as Prevention (TasP) refers to the use of HIV medicine to decrease the risk of HIV transmission. People living with HIV who take HIV medicine exactly as prescribed can suppress their HIV viral load to an undetectable level (<200 copies/ml), reducing the risk of HIV transmission to others (i.e. Undetectable = Untransmittable, U=U).

To learn more about TasP, please click here.


HIV Education Events

The National HIV Programme (NHIVP) regularly hosts seminars and education events to raise HIV awareness and knowledge in the community. You may find all the HIV-related past events here.

The annual events are:

  • HIV Community Engagement Forum - The HIV Community Engagement Forum aims to bring together people from all walks of life, such as infectious disease specialists, general healthcare professionals, members of the community working with HIV populations, and the general public, to engage in dialogues and discussions in order to raise awareness and combat various misconceptions surrounding HIV.

  • World AIDS Day - World AIDS Day (WAD) started in 1988 and takes place on 1 December each year. It is an international day for people worldwide to unite in the fight against HIV, to show support for people living with HIV, and to commemorate those who have died from an AIDS-related illness. Every year, NHIVP and Enhanced HIV Programmes at public healthcare institutions commemorate WAD through activities to raise awareness about HIV, challenge misconceptions about HIV transmission and infection, and develop empathy and solidarity between people living with HIV and healthcare workers.

To receive information about NHIVP's events, please email:

Articles in Media and Publications

  1. CNA, 2023: New HIV infections among Singapore residents fall to lowest level since 1998

  2. Berita Harian, 2023: HIV can be treated

  3. The Straits Times, 2022: With early and effective treatment, people with HIV live no differently from others

  4. Her World, 2022: Health matters: Why we need to destigmatise attitudes towards HIV

  5. NCID Intelligence, 2022: Living with HIV in an Age of COVID-19

  6. NCID, 2021: Ending HIV (and its stigma) in Singapore - the ambitious goal of the NHIVP

  7. The Straits Times, 2020: HIV and COVID-19: Lessons from two plagues

  8. The Straits Times, 2019: Need to maintain trust with people living with HIV

National HIV Recommendations & Guidelines

Developed by the NHIVP, the following recommendations and guidelines are used to promote HIV prevention, treatment and care:

  • HIV Testing Recommendations

  • Pre-Exposure Prophylaxis (PrEP) Guidance

  • Antiretroviral Therapy (ART) Recommendations

  • Primary Care Recommendations

You may find the full text here.

The NHIVP, along with various partners, consistently develop education campaigns aimed at debunking HIV myths and misconceptions, promoting HIV prevention and treatment, as well as stopping HIV stigma.

HIV doesn’t differentiate (2022 & 2023)

FY22 HIV campaign (single or married).jpgYounger or Older_1500px.jpgCasual or Serious.jpgFling or more.jpg

Content Pieces

YearContent Pieces

With early and effective treatment, people living with HIV can lead lives no different from others (2021)


Content Pieces

It’s Time to Spread the Facts (2019)


Click the poster to watch the campaign videos.

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