Development and evaluation of a blocking ELISA for serological diagnosis of equine infectious anemia

Equine infectious anemia (EIA) is an important viral disease characterized by persistent infection in equids worldwide. Most EIA cases are life-long virus carriers with low antibody reactions and without the appearance of clinical symptoms. A serological test with high sensitivity and specificity is required to detect inapparent infection. In this study, a B-cell common epitope-based blocking ELISA (bELISA) was developed using a monoclonal antibody together with the EIAV p26 protein labelled with HRP. The test has been evaluated against the standard and with field serum samples globally. This bELISA test can be completed within 75 min, and the sensitivity is higher than those of either the AGID or one commercial cELISA kit. This bELISA assay was 8–16 times more analytically sensitive than AGID, and 2 to 4 times more analytically sensitive than one cELISA kit by testing three sera from the USA, Argentina, and China, respectively. The 353 serum samples from Argentina were tested, in comparison with AGID, the diagnostic sensitivity and specificity of our bELISA assay were 100% (154/154) and 97.0% (193/199), respectively, and the accuracy of the bELISA test was 98.3%. The bELISA test developed in this study is a rapid, sensitive, specific method for the detection of EIAV infection, and could be a promising candidate for use in the monitoring of the EIA epidemic worldwide.

Instituto de Virologia

Fil: Zhe, Hu. Chinese Academy of Agricultural Sciences. Harbin Veterinary Research Institute. State Key Laboratory of Veterinary Biotechnology; China

Fil: Zhe, Hu. WOAH Reference Laboratory for Equine Infectious Anemia; China

Fil: Kui, Guo. Chinese Academy of Agricultural Sciences. Harbin Veterinary Research Institute. State Key Laboratory of Veterinary Biotechnology; China

Fil: Cheng, Du. Chinese Academy of Agricultural Sciences. Harbin Veterinary Research Institute. State Key Laboratory of Veterinary Biotechnology; China

Fil: Jinhui, Sun. Chinese Academy of Agricultural Sciences. Harbin Veterinary Research Institute. State Key Laboratory of Veterinary Biotechnology; China

Fil: Jinhui, Sun. Northeast Agricultural University; China

Fil: Naletoski, Ivancho. International Atomic Energy Agency. Animal Production and Health Section. Joint FAO/IAEA Centre for Nuclear Applications in Food and Agriculture, Department of Nuclear Sciences and Applications; Austria

Fil: Xiaoyu, Chu. Chinese Academy of Agricultural Sciences. Harbin Veterinary Research Institute. State Key Laboratory of Veterinary Biotechnology; China

Fil: Yuezhi, Lin. Chinese Academy of Agricultural Sciences. Harbin Veterinary Research Institute. State Key Laboratory of Veterinary Biotechnology; China

Fil: Xuefeng, Wang. Chinese Academy of Agricultural Sciences. Harbin Veterinary Research Institute. State Key Laboratory of Veterinary Biotechnology; China

Fil: Barrandeguy, Maria Edith. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Virología; Argentina

Fil: Barrandeguy, Maria Edith. Universidad del Salvador. Facultad de Ciencias Agrarias y Veterinarias; Argentina

Fil: Miño, Samuel. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Virología; Argentina

Fil: Wen, Wang. Animal Health Supervision Institute of Xinjiang Uygur Autonomous Region; China

Fil: Lau, Patrick Imtung. Agriculture Fisheries and Conservation Department. Equine Disease Division; China

Fil: Wernery, Ulrich. Central Veterinary Research Laboratory; Emiratos Arabes Unidos

Fil: Raghavan, Rekha. Central Veterinary Research Laboratory; Emiratos Arabes Unidos

Fil: Xiaojun, Wang. Chinese Academy of Agricultural Sciences. Harbin Veterinary Research Institute. State Key Laboratory of Veterinary Biotechnology; China

Fil: Xiaojun, Wang. WOAH Reference Laboratory for Equine Infectious Anemia; China