Procedurally similar competitive immunoassay systems for the serodiagnosis of Babesia equi, Babesia caballi, Trypanosoma equiperdum, and Burkholderia mallei infection in horses.

The research developed and assessed procedurally similar competitive enzyme-linked immunoassay (cELISA) methods for diagnosis of Babesia equi, Babesia caballi, Trypanosoma equiperdum, and Burkholderia mallei infections in horses. The findings suggest that the cELISA method is technically more reproducible, objective, and convenient for diagnosis in qualifying animals for international movement and disease eradication programs than currently used methods.

Development of the cELISA Methods

• The researchers developed similar competitive enzyme-linked immunoassay (cELISA) methods for the diagnosis of four different infections: Babesia equi, Babesia caballi, Trypanosoma equiperdum, and Burkholderia mallei, in horses. These infections are known respectively as piroplasmosis, dourine, and glanders.
• cELISA methods use a competitive process where a labeled reagent competes with unlabeled antigen in a sample for binding specific antibody sites. This is a common method used in clinical diagnostics for the detection of certain compounds (antigens) in a specimen.

Testing and Analysis

• The test specificities for these cELISA methods were found to be consistently high, with Babesia equi at 99.2%, Babesia caballi at 99.5%, Trypanosoma equiperdum at 98.9%, and Burkholderia mallei at 98.9%.
• These results suggest that these cELISA methods are highly accurate and reliable, with a very low likelihood of producing false positive results.

Comparison with Existing Methods

• The researchers also compared the cELISA methods with the existing complement fixation (CF) methods.
• They found that the concordances between the CF and the cELISA methods for the serodiagnosis of the four infections were relatively high, indicating a strong agreement between the two methods.
• However, the researchers note that the cELISA methods may be a more technically reproducible, objective, and convenient approach than the CF methods currently in use.

Implications of the Research

• The use of the cELISA method also solved the issues related to testing hemolyzed or anticomplementary sera, which are types of blood samples that can influence the results of a test.
• This suggests that the cELISA method can be used in various settings such as in checking animals for diseases during international transportation or in disease eradication programs.