What is the initial screening test for HIV diagnosis?

The initial screening test for HIV diagnosis is the ELISA (Enzyme-Linked Immunosorbent Assay). This test is designed to detect antibodies to the HIV virus in the blood. It is known for its high sensitivity, allowing it to effectively identify most individuals who are infected with HIV. When a person is exposed to the virus, the immune system typically produces antibodies, and the ELISA test is capable of identifying these antibodies within a few weeks after infection.

In addition to being an effective screening tool, one of the key advantages of the ELISA is that it can be performed in large batches, which makes it suitable for widespread screening in various healthcare settings. A positive result from an ELISA test usually prompts a follow-up test to confirm the diagnosis, often utilizing methods with higher specificity, such as the Western blot or an HIV RNA test, like PCR. However, the ELISA remains the standard starting point for HIV diagnosis due to its broad availability and efficiency in detecting the virus early, making it an essential tool in public health efforts for HIV prevention and management.