[Laboratory testing strategies for human immunodeficiency virus (HIV) in blood donors]

Objective To propose the blood detection strategies for human immunodeficiency virus (HIV) among blood donors, and provide reference for the detection, early diagnosis and transmission blocking of HIV. Methods A total of 117 987 blood samples from blood donors were screened using the third- and fourth-generation ELISA HIV detection reagents. Western blot analysis was used to verify the reactive results of the third-generation reagent alone, or both the third-generation and fourth-generation reagents. HIV nucleic acid test was carried out for those with negative test results of the third- and fourth-generation reagents. For those with positive results of the fourth-generation reagent only, nucleic acid test followed by a confirmatory test by Western blot analysis was carried out. Results 117 987 blood samples from blood donors were tested by different reagents. Among them, 55 were tested positive by both the third- and fourth-generation HIV detection reagents at the same time, accounting for 0.047% and 54 cases were confirmed HIV-positive by Western blot analysis, and 1 case was indeterminate, then turned positive during follow-up testing. 26 cases were positive by the third-generation reagent test alone, among which 24 cases were negative and 2 were indeterminate by Western blot analysis. The band types were p24 and gp160 respectively detected by Western blot analysis, and were confirmed to be HIV negative in follow-up testing. 31 cases were positive by the fourth-generation HIV reagent alone, among which 29 were negative by nucleic acid test, and 2 were positive according to the nucleic acid test.Western blot analysis was used to verify that the two cases were negative. However, after 2~4 weeks, the results turned positive when the blood sample was retested by Western blot analysis during the follow-up of these two cases. All the specimens that were tested negative by both the third- and fourth-generation HIV reagents were validated negative by HIV nucleic acid test. Conclusion A combined strategy with both third- and fourth-generation HIV detection reagents can play a complementary role in blood screening among blood donors. The application of complementary tests, such as nucleic acid test and Western blot analysis, can further improve the safety of blood supply, thus contributing to the early diagnosis, prevention, transmission and treatment of blood donors potentially infected by HIV.