Evaluation of immunochromatographic assay systems for rapid detection of hepatitis B surface antigen and antibody, Dainascreen HBsAg and Dainascreen Ausab.

We evaluated two immunochromatographic assays (ICAs), Dainascreen HBsAg for detecting human hepatitis hepatitis B surface antigen (HBsAg) and Dainascreen Ausab for detecting human hepatitis B surface antibody (anti-HBs) in human serum. The ICA systems are composed of a comb-shaped device that contains nitrocellulose strips on which complexes of HBsAg and anti-HBs can be visualized. The results can be read within 15 min of incubation. The limit of detection for HBsAg was 3.1 ng/ml and that for anti-HBs was 42 mIU/ml. Results of HBsAg detection agreed completely with those of conventional enzyme immunoassays (EIAs) and showed a 100% sensitivity (158 of 158 samples) and a 100% specificity (304 of 304 samples). The Dainascreen Ausab detected 184 of the 199 EIA-positive samples (sensitivity, 92.5%) and yielded 6 positive results among the 281 EIA-negative samples (specificity, 97.9%). The ICA systems are rapid and sensitive methods for detecting HBsAg and anti-HBs. They are low-cost systems that need no complex instrumentation for analysis and can be recommended for routine use in clinical microbiology laboratories.