What to Do After Possible HIV Exposure: A Guide to HIV PEP in Singapore

Introduction

Contracting HIV remains one of the biggest fears in most of us due to the incurable state of the condition and associated disease stigma. HIV infection is still a global public health concern, with ongoing transmission and infectivity worldwide. Hitherto, HIV have claimed approximately 44.1 million lives, based on the World Health Organization (WHO).

There is no cure for HIV infection. Once a person contracted HIV, they will have the infection for life. HIV infection can be contracted through unprotected sexual intercourse, body fluid, mother-to-child vertical transmission, needle sharing/ needle stick injuries or (rarely) blood transfusion with a HIV-infected person.

Despite being incurable in disease nature, we can prevent HIV. PEP medication is the next best chance to halt acquisition of HIV following exposure to the infection. PEP, when given promptly can be life-saving. 

HIV Risk After Unprotected Sex 

The risk of contracting HIV following unprotected intercourse with a person with HIV infection is estimated by below:

The risk of HIV infection in oral sex is low with limited statistic estimation of the risk, though there are documented reports of HIV infection cases acquired through oral intercourse. The risk of oral sex increases if there is a history of ejaculation in a receptive oral intercourse person. 

Other risk factors of acquiring HIV when exposed to a HIV person include:

• Having open wound, cuts and sores or ulcers over the genital region;
• Having concurrent STD(s) that are not treated;
• Sexual partner's HIV viral load is high or untreated HIV infection;
• Simultaneous use of drugs (chemsex), sharing of syringes/ needle injections with person with HIV.

As everyone's encounter risk may differ, you may wish to discuss with your trusted healthcare provider for further evaluation of your risk of exposure to HIV and/ or other STDs.

What is HIV PEP?

HIV PEP is the short form of post-exposure prophylaxis. 'Prophylaxis' means 'prevention' or 'containment' of further spread of disease. In the context of possible HIV infection, PEP medication is used to prevent the acquisition of HIV infection following a possible exposure. 

HIV PEP should be started within the first 72 hours after possible exposure to HIV. The earlier one starts PEP, the better effect it is as every hour makes a difference.

Although HIV PEP is effective in reducing the risk to HIV, it should be used in emergency situation (after an accidental exposure occurred) and not meant to be used in those who may have frequent HIV exposure. 

When should I consider PEP?

One should consider PEP if they do not have baseline HIV infection (or who is not aware of his/her HIV status), and in the last 72 hours have:

• potential exposure to HIV via sexual intercourse;
• potential exposure to HIV via non-sexual route (such as occupational exposure);
• Sharing of needles and syringe in injecting drugs (drug abusers);
• Sexually assaulted

If you are concerned of possible exposure to HIV, do not hesitate to reach out to your healthcare provider for PEP without any delay.

Why is the 72-Hour Window Critical for HIV Prevention?

When a person is exposed to HIV virus through the skin or mucous membrane, a type of body's immune cells known as macrophages attempt to engulf and contain the virus. As the immune cells circulate along the lymphatic drains and lymphatic nodes of the body, the HIV viruses will circulate, replicate and expand to the surrounding lymph nodes within 2-3 days after exposure. This is the critical moment that appropriate medical intervention can halt the progression of HIV. Within the next 3-5 days, the virus will be disseminated to other parts of the body causing permanent infection, establishing an irreversible HIV status. 

Administrating PEP medication into the body as soon as possible, or at least within the first 72 hours (3 days) timeframe has been shown to be effective in curbing further HIV replication and establishment in the body, hence effectively reduces a person's risk of contracting HIV infection.

This is why starting on PEP is time-sensitive, and every hour counts.

How Doctors Assess HIV Transmission Risk 

Your Healthcare provider will obtain a medical history involving

• History and timing of potential exposure to HIV infection;
• Previous medical history/long-term medication conditions;
• Medication history;
• Social history (including sexual history, history of recreational drug or alcohol use)

Depending on individual history, your doctor may follow up with physical examination of the genital region and other parts of the body to evaluate for any symptoms or signs of HIV and STD infections.

In some, your doctor may offer baseline blood tests, rapid STD tests to evaluate your medical situation.

Your doctor will then discuss with you on your individual risk of HIV exposure and if needed/ appropriate, offer PEP medication to you.

What to Do or Bring Before Appointment for PEP consultation?

Generally, there is no major preparation required before your PEP consultation appointment. 

Any recent blood tests including liver and kidney functions, HIV tests/ STD tests can be useful for your doctor to evaluate further your suitability of PEP medications. If you are on long term medications or supplements, you can bring along the name of the drugs to share with your doctor.

Why should one consider PEP?

Although there are medical advancement in the management of long term HIV infection, HIV remains one of the infectious diseases that is still incurable. Once a person is infected with HIV, one can develop multiple health complications and succumb to end-stage AIDS disease.

To make things worse, the status of HIV is associated with detrimental social implications. HIV may affect relationships as it can be passed to spouses and posed a danger during pregnancy to the newborn.  

The fear of HIV discrimination and long-term health sequelae, social impact and moral conscience can may result in mental stress, breakdown and anxiety to a person who may have contracted HIV. 

PEP is the only chance in the first 72 hours to 'make things right', reduce risk of contracting HIV and potentially save a person's life. 

Contact Us

If you’ve had a possible HIV exposure, timely action is crucial. At DB Clinic, our team provides confidential consultations  to help you understand HIV PEP in Singapore and discuss the options available.

References:

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