Evaluation of indirect immunofluorescence assay for the diagnosis of bacterial agent of glanders

Glanders is one of the most dangerous and oldest communicable zoonotic diseases and causes many deaths in equines, carnivores, and humans. Because of the sudden increase of the rate of glanders in the Middle East and the use of its pathogen as a biological weapon, the detection of this disease is necessary by use of rapid diagnostic tests. This study was conducted to diagnose causative agent of glanders by immunofluorescence method in horses.
Burkholderia mallei strain was cultured in glycerinated gelose and bouin medium to produce mallein in the Department of Research and production of tuberculin and mallein in Razi Vaccine and Serum Research Institute, then identified using molecular techniques (Such as DNA extraction and PCR). A suspension was prepared and then heated to inactivate the bacteria. A bacterial smear was prepared and fixed on a slide. By injecting the microbial suspension to the horse, an antibody produced which was added to an anti-horse conjugated with fluorescein. The slide was examined using an immunofluorescent microscope.
There were clearly luminous bacilli on the slide with positive serum, but dark bacilli were hardly observable on the slide with negative serum.
The results of observation of prepared slides from the positive and negative serum by ELISA, Malleination and CFT tests are match with the results of the immunofluorescence method and the validity of this method was confirmed. As a result, this method can be used for diagnosis causative agent of glanders.