Sensitivity of antigen ELISA test for detecting Trypanosoma evansi antigen in horses in the subtropical area of Argentina.

The research article evaluates the effectiveness of a specific enzyme immunoassay test, known as antingen ELISA, in detecting a parasitic disease in horses within a subtropical region of Argentina.

Research Methodology

• The experimental base of this research focused on the use of an antigen detection enzyme immunoassay (Ag-ELISA) test constructed from a monoclonal antibody specific to the Trypanosoma brucei group.
• The study used three horses and two mules as test subjects, which were infected with Trypanosoma evansi.
• The antigen levels in the blood of these animals were monitored and recorded at two intervals after they got infected; 7 days and 21 days.

Major Findings

• The findings indicated an increase in the antigen levels as the disease progressed in the infected animals.
• Furthermore, it was discovered that a high antigen level persisted even when parasitemia (the presence of parasite in the blood) was low or when the parasites were undetectable.
• Nevertheless, when effective drug treatments were deployed, the antigens were cleared from the serum. On the other hand, the antigen persisted if the treatment was ineffective.

Field Testing and Results

• The researchers then tested the accuracy of Ag-ELISA test during six outbreaks of “mal de caderas” (a lethal horse disease caused by T. evansi), involving 125 horses.
• The standard parasite detection methods found T. evansi in 78 horses out of 125 and out of these 78 infected horses, antigenemia was detected in 58 by using the Ag-ELISA test.
• This implies that the sensitivity rate of the Ag-ELISA test in detecting the parasite varied between 63% and 100% for the separate outbreaks.
• The combination of Ag-ELISA and standard parasitologic methods enabled the identification of 93 infected animals out of the total 125.

Conclusion

• In conclusion, this research shows that the Ag-ELISA test is not only useful in diagnosing T. evansi in horses, but it also assists in evaluating the efficiency of drug treatments.