Third generation tests are known as HIV antibody tests. This test is only accurate three months after exposure, because this is how long it takes your body to produce enough antibodies for it to show up in a test. Fourth-generation HIV tests are different from third-generation tests, which can only detect HIV antibodies. How accurate is the HIV blood test accuracy is so high that its unusual to have a positive result when you dont have HIV, or to have a negative result when you do have the virus. Still, it is possible. Of the 58 samples tested, the third-generation rapid tests achieved a sensitivity of only 5.2% to 25.9%, meaning that the majority of such infections would be Repeat HIV testing in the third trimester is recommended for pregnant people with negative initial HIV tests who are at increased risk of acquiring HIV, Macias D, Gaffney D, et al. Diagnostic accuracy of fourth-generation ARCHITECT HIV Ag/Ab combo assay and utility of signal-to-cutoff ratio to predict false-positive HIV tests in pregnancy. There is a good chance of a 3rd generation lab based test being able to detect the virus in your body on day 41 after exposure to the HIV virus. The 3rd generation HIV test is a conventional method that detects both IgM and IgG antibodies against the virus, contributing to early diagnosis..Third generation assay only test for the IgM and IgG The human immunodeficiency virus (HIV) is the causative agent of acquired immunodeficiency syndrome (AIDS) and has been a major global burden for over four decades. 1,2 HIV is transmitted through sexual contact, contaminated blood and blood products or from an HIV-infected mother to her child before, during and after birth. 3 Diagnosis of an HIV infection can be made as early as 2 - 3 weeks According to the CDC, WebMD and HealthLine the window period for the RNA/NAT test for HIV is 10-33 days meaning you would need to wait till the 34th day to get a conclusive result. You don't need to wait 6 months or 3 months for this test here. Antibody/Antigen 4th Gen test is 18-45 days meaning you'd need to wait till the 46 day in order to This is because the p24 antigen is detectable before HIV antibodies. In addition, the fourth-generation test can rule out an HIV infection 5.5 weeks earlier than third-generation tests. Most people will get an accurate test result with third- or fourth-generation tests three to four weeks after an exposure to HIV. However, not everyone will. The following different types of tests are used commonly in commercial HIV testing: Types of tests Elisa test (3rd generation) Tests for antibodies only Combo test (4th generation) - Tests for antibodies and antigen -The antigen component shortens the window period P-24 AG test Tests for antigen only This used to involve waiting 3 to 4 weeks before taking an HIV test (see Figure 6). However, 2020 UK guidelines now recommend waiting 6 weeks. This is because 4th generation HIV tests (antigen/antibody) will detect 99% of infections at 6 weeks - compared to 95% of infections 4 weeks after exposure. A negative test after four weeks needs to be The fourth generation Enzyme Immuno Assays (EIAs) identify 93 % and the third generation EIAs [Rapid Diagnostic Test (RDT) kits] (also identify) 63 % of all recent infections . Although RDT kits have the lowest detection ability, they remain the preferred assay for HIV testing in many countries. lZ4e2.