Department of Laboratory, Guangzhou Quarantine Bureau of PRC, Guangzhou, China

Between June 1986 and May 1996 we tested a total of 291713 samples which were part of the immigration applicants HIV initial test programme. Among which 126 cases were detected positive. By using the WB method, we confirmed 112 cases being HIV positive, including 4 cases being susceptibly positive, producing an accuracy of 88.9%. However, 14 cases were confirmed negative, producing a false positive rate of 11.1%.

The HIV test is a basic method for diagnosing whether the blood has been infected with HIV and hence a major basis for the diagnosis of AIDS. Although the HIV initial test can help to discover most cases infected by HIV, it lacks high specificity. For this reason, the initial test may wrongly diagnoses a case as being positive. Therefore, a sample must be confirmed using a confirmation test after being diagnosed as positive with the initial test.