How to test for AIDS
Jun 30, 2025
Source: Cainiu Health
Dr. Liu Feng
Introduction
Under normal circumstances, methods for testing for AIDS include HIV antibody testing, HIV drug resistance testing, HIV nucleic acid qualitative and quantitative testing, absolute CD4+ T lymphocyte count, and HIV antigen testing. In daily life, it is important to use condoms correctly, which helps prevent the spread of AIDS, avoid having multiple sexual partners, and reduce the occurrence of unsafe sexual behaviors.
Generally, the methods for testing HIV/AIDS include HIV antibody testing, HIV drug resistance testing, HIV nucleic acid qualitative and quantitative testing, absolute CD4+ T lymphocyte count, and HIV antigen testing. A detailed explanation is as follows:
1. HIV Antibody Testing
This is a commonly used testing method, including screening tests and supplemental tests. Screening tests include enzyme-linked immunosorbent assay (ELISA), chemiluminescence or immunofluorescence assays, and rapid tests. These tests usually involve collecting venous blood, although saliva or urine samples may also be used. If the screening test is positive, a supplemental test should be conducted, typically using methods such as immunoblotting to confirm results and improve testing accuracy.
2. HIV Drug Resistance Testing
Drug resistance testing methods include genotypic and phenotypic testing, with genotypic testing being more commonly used domestically and internationally. By sequencing and analyzing the HIV viral genome, drug-resistant gene mutations can be identified. This information can be used to evaluate the effectiveness of antiviral therapy, improve drug resistance issues, and guide clinical adjustments to antiviral treatment regimens.
3. HIV Nucleic Acid Qualitative and Quantitative Testing
Using techniques such as polymerase chain reaction (PCR), HIV viral RNA in the blood is tested by collecting venous blood samples. Qualitative testing is primarily used to test individuals who are screening-negative but suspected of being infected. Quantitative testing, also known as viral load testing, can assess disease progression, evaluate the effectiveness of antiviral therapy, and detect recurrent cases.
4. Absolute CD4+ T Lymphocyte Count
HIV/AIDS damages the human immune system, leading to a decrease in CD4+ T lymphocyte count. Using flow cytometry to count the number of CD4+ T lymphocytes in the blood can assess the immune function of infected individuals, assist in monitoring disease progression, and provide a basis for developing and adjusting treatment plans.
5. HIV Antigen Testing
HIV antigen testing primarily detects the p24 antigen of the human immunodeficiency virus. Using specific antibodies against the p24 antigen, the p24 antigen in the sample can be detected through methods such as the double-antibody sandwich technique. During the early stages of infection when the virus replicates extensively, the p24 antigen can be detected in the blood.
In daily life, correct use of condoms can help prevent the spread of HIV/AIDS. Avoiding multiple sexual partners and reducing unsafe sexual behaviors are also important preventive measures.
