Development and application of a colloidal gold dual immunochromatography strip for detecting antibodies against African swine fever virus.

African swine fever (ASF) virus (ASFV) is widely prevalent globally. Due to its rapid onset and the absence of effective vaccines or therapeutic drugs, ASFV has caused significant economic losses to the global pig industry. In recent years, the less pathogenic ASFV△CD2v strain with the deleted or mutated EP402R gene has become gradually more prevalent, which has further increased the difficulty of ASFV control. Colloidal gold immunochromatographic strips (ICSs) allow rapid, sensitive, and low-cost testing that does not rely on special equipment or skilled personnel, and are often used in on-site clinical testing. However, commercially available ICSs for on-site use only determine the presence or absence of ASFV antibodies and cannot distinguish between ASFV△CD2v and wild-type ASFV infections. To address these problems, we developed a double-target colloidal gold ICS with two detection lines for the detection of p30 and CD2v protein antibodies. This colloidal gold dual ICS could specifically identify antibodies against p30 and CD2v proteins within 10 min without any equipment. The colloidal gold dual ICS exhibited high specificity, sensitivity, stability and good test accuracy (99.823 % for p30 and CD2v proteins). Compared with existing ICSs, the colloidal gold dual ICS exhibited significant advantages in differentiating ASFV△CD2v and wild-type ASFV infections. The findings indicate the promising potential of the novel colloidal gold dual ICS for rapid on-site detection of ASFV antibodies and differentiation of ASFV△CD2v and wild-type ASFV infections. The novel colloidal gold dual ICS could improve the effectiveness of ASFV control.