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SD Bioline 4th Gen antigen and antibody fingerprick test

Question: 

Hi!

I am a student here in New Zealand. I am now very anxious and devastated on what happened to me, I even filed for a leave which is 3 months because I cannot focus on my studies.

Here is my story :
I met a guy using my Grindr application, He invited to me stay at his place. an long story short we did Deep kissing and Oral Sex both giving an receiving. he did not come in my mouth, although pre-cum is possibly there. What really scares me is that after we did the incident he told me that he is HIV positive for 15 years.

I don't care about how long, what makes me anxious is the possibility of it being transmitted to me :(

HERE ARE MY QUESTIONS:

1. I tested SD Bioline 4th generation HIV ag/ab rapid fingerprick test at 9, 25, and 35 ( 5 weeks ) days post exposure I tested negative from all of those. do you think if I will test again in 6 weeks it will be conclusive and reliable?

2. what is the probability that my result from 5 weeks and 6 weeks change in 3 months? when you said that WHO and many specialist consider 6 weeks conclusive.

Answer: 

Hello,

Thank you for contacting the AIDS Vancouver Helpline as your source for HIV/AIDS related information. I am very sorry to hear about your stress and anxiety. I can sense that you are extremely worried about this situation and I would be happy to help you by answering your questions.

First, please know that HIV is very difficult to contract. Just because you engage in sexual intercourse with a person living with HIV, it does not mean that you will get HIV for sure. With that said, receiving oral sex is considered a negligible risk. This means that while there is a risk for getting HIV due to the exchange of body fluids, there has never been any confirmed reports of getting HIV in this way. On the other hand, giving oral sex is considered a low risk. This means that there have been few reports of infection occurring in this way. With this said, your overall risk is considered low. Since your risk is considered low and because you had intercourse with a person living with HIV, it is good that you have been tested to ensure your health and well-being.

I will now answer your questions. Please refer to the tables I will be providing to help you understand.

The 4th generation test is excellent and very reliable. It is also called the COMBO or DUO test. This test detects both HIV antigens and antibodies. Antigens are released by your body in response to being infected with HIV. Antigens are present immediately after infection and last for a few weeks. After that, antibodies are formed within the next 4-6 weeks, with most being formed at 21-25 days. It is 99.9% accurate after the conclusive period. You are correct when you say that this test is considered by many HIV specialists and the World Health Organization saying it is conclusive at 6 weeks. However, AIDS Vancouver guidelines (based on the BC Center for Disease Control) still maintain that all HIV tests, including the 4th generation, are conclusive at 12 weeks or 3 months after your last high risk exposure. Since you live in New Zealand, it may be helpful to partner with your local medical professional to determine the guidelines set by your country.

While it is also great to hear that this test is now being performed as a rapid test via a simple finger prick, HIV testing using a finger prick rather than laboratory work means that there is an opportunity lost for other testing such as STI's and Hepatitis. Some of these other tests are performed using blood testing performed in a laboratory. AIDS Vancouver does recommend that all sexually active people be tested on a regular basis for all STI's and HIV. I encourage you to partner with your Doctor so that you can be tested for other STI's and Hepatitis if you haven't already done so.

4th Generation Test

Test Name
Method
Window Period
Conditions
4th Generation EIA Blood test that looks for antibodies AND p24 protein antigens. Commonly referred to as the "combination," "combo" or "DUO" test. Antigen (ag) test - P24 protein is detectable immediately after infection, & only for the first few weeks. The antibody (ab) test has a window period of 4-12 weeks. Most HIV specialists consider this test to be conclusive at 6 weeks. This is the screening methods used in Victoria and many parts of Ontario. Vancouver still uses the 3rd generation test unless it was a high risk exposure. The testing centre will evaluate people on a case by case basis to assess if this test would be helpful in early detection. Official HIV testing guidelines still recommend re-testing at 12 weeks for conclusive results. Accuracy is 99.9%
Test Name
Method
Window Period
Conditions
4th Generation EIA Blood test that looks for antibodies AND p24 protein antigens. Commonly referred to as the "combination," "combo" or "DUO" test. P24 protein is detectable immediately after infection but only for the first few weeks. The antibody (ab) test has a window period of 4-12 weeks post exposure. This test is widely available in North America. Most HIV specialists consider this test to be conclusive at 6 weeks but official HIV testing guidelines still recommend re-testing at 12 weeks for conclusive results. Conclusive at 3 months post exposure.

I cannot give a probability for a change in results from 6 weeks to 3 months. I will say that 6 weeks is a good indicator of your status. Again, I encourage you to speak to your local medical professional regarding your country's guidelines for the 4th generation test and its conclusive period. You can also contact the New Zealand AIDS Foundation for information closer to home. They offer testing and counselling services which you could benefit from.

With regards to having intercourse with a person living with HIV, please know that with modern medication, there are many people who are considered Undetectable. This means that a person is on their antiretroviral medications and following their regimen to a point there their viral load levels are so low that they are barely detectable. When someone is Undetectable, they have a lower to no chance of passing on HIV from themselves to another person. What is even better is that many people who are undetectable can lead healthy lives that are just as long and if not, even longer than someone who is not living with HIV. This is great news and a wonderful progression in HIV/AIDS care. If you want to read more about this, please refer to the link provided.

I hope I have answered your questions and that you feel better. Please feel free to contact us if you have any more questions.

Best wishes,

Mary

AIDS Vancouver Online Helpline
helpline.aidsvancouver.org
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