HIV Combo (Antigen And Antibody) Test
Understanding HIV Combo (Antigen And Antibody) Test
What is HIV Combo (Antigen And Antibody) Test?
An HIV Combo (Antigen And Antibody) Test is an advanced screening test for Human immunodeficiency virus (HIV) 1 & 2 antibodies and HIV p24 antigen. This test is done to detect the presence of the HIV 1 & 2 virus in the blood. The test helps in the early diagnosis if you suspect an accidental exposure to this virus or with someone who is infected and helps manage the disease.
HIV is a virus that attacks the body’s immune system. HIV is transmitted through sexual contact, by exposure to the blood of AIDS-infected individuals, or from an infected mother to an unborn baby. If left untreated, it can lead to AIDS (acquired immunodeficiency syndrome).
An antigen is a foreign substance that triggers the body to produce specific proteins called antibodies. With an HIV infection, the p24 protein is the antigen that most commonly triggers the body's antibody response. During the first few weeks after an individual gets exposed to the virus, the p24 antigen becomes detectable in their blood. After 2-8 weeks, the body starts producing antibodies against this antigen, and the levels of both the antibody and antigen tend to decrease. HIV Combo (Antigen And Antibody) Test is very accurate for early detection of whether or not an individual has been infected with HIV. The p24 antigen is the first marker of the presence of HIV in the body. Therefore, this test can detect an infection earlier than an antibody test alone.
HIV Combo (Antigen And Antibody) Test is advised for people who are at an increased risk of HIV infection such as those who have an HIV-positive sex partner, have multiple sexual partners, are homosexual, and who share needles frequently. The test may also be performed when there are symptoms like fever, chills, nausea, rash, night sweats, muscle aches, oral thrush, sore throat, fatigue, unintentional weight loss, swollen lymph nodes, and mouth ulcers. It should be noted that a person may not show any symptoms if the infection is recent (or acute). Also, annual screening is advised for those who are identified to be at high risk for HIV infection.
You may talk to your doctor about all the pre-test instructions. Fasting is not required before getting an HIV Combo (Antigen And Antibody) Test; which means you can eat or drink normally as per your daily routine. However, a duly filled consent form for HIV testing & Pre-test counseling (Annexure - CR/01) is mandatory at the time of sample collection. This form can be provided by the laboratory personnel (phlebotomist) before sample withdrawal. It entails important information related to your personal details, medical history, and pre-test (before the test) counseling details.
Discuss your specific test results with your doctor. An HIV Combo (Antigen And Antibody) Test results are reported as positive or negative. Follow-up testing is often necessary in case of positive test results. Although there is no effective cure for HIV, the right treatment can help an infected person lead a healthy life while living with the virus.
What is HIV Combo (Antigen And Antibody) Test used for?
An HIV Combo (Antigen And Antibody) Test is done:
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To screen for HIV infection.
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To know your HIV status if you are pregnant or planning to get pregnant.
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If you are diagnosed with Hepatitis B, C, Tuberculosis, or any other sexually transmitted disease (STD), or tuberculosis.
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To differentiate HIV-1 and HIV-2 antibodies in specimens of serum that show reactive results with third and fourth-generation HIV serologic assays.
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To help confirm the presence of HIV in donated blood or plasma.
What does HIV Combo (Antigen And Antibody) Test measure?
An HIV Combo (Antigen And Antibody) Test simultaneously detects HIV p24 antigen and antibodies associated with HIV 1 & 2. The HIV p24 antigen is the most abundant HIV protein and its detection is used clinically to diagnose an HIV infection early on since HIV-specific antibodies are not detectable in a very recently acquired infection. HIV-1 was discovered first and is the most widespread, whereas HIV-2 is more than 55% genetically different from HIV-1. The transmission rate of HIV-2 is also slower than HIV-1. This test also helps to differentiate between the two HIV infections.
Interpreting HIV Combo (Antigen And Antibody) Test results
Interpretations
- A negative HIV antibody test usually indicates that a person does not have HIV infection. However, it only means that there is no evidence of disease at the time of the test.
- If someone tests positive on both the initial screening and supplemental testing, it is considered as a definite case of infection with HIV.