Performance of an Immunochromatographic Test (ICT) in Comparison to Some Commonly Used Serological Tests for the Diagnosis of Brucellosis in Dromedary Camels (Camelus dromedarius)

Microorganisms. 2019 Nov 20;7(12):591. doi: 10.3390/microorganisms7120591.

Abstract

Serological tests may represent an essential tool for the diagnosis of camel brucellosis; however, concerns arise in the scientific community regarding the direct transposition from cattle and small ruminants without adequate validation. The present study was made to compare four serological tests for the diagnosis of brucellosis in dromedary camels (Camelus dromedarius). In terms of sensitivity, our results show that the Immunochromatographic Test (ICT) shows the higher value of sensitivity, 98.67% (95% Confidence Level (C.L): 94.36%-99.99%), followed by the Fluorescence Polarization Assay (FPA) with 95.05% (95% C.L: 88.23%-99.51%), then the Competitive Enzyme-Linked Immunosorbent Assay (c-ELISA) with 94.94% (95% C.L: 88.25%-99.45%) and, finally, the Rose Bengal Test (RBT) with 68.95% (95% C.L: 56.55%-80.69%), which is the only test showing a significantly lower sensitivity compared to the others. On the other hand, our study revealed no significant difference in terms of specificity between all the tests under study, with a range from 99.06% (95% C.L: 98.34%-99.64%) for the ICT to 99.92% (95% C.L: 99.64%-100%) for the RBT. The ICT was found to be comparable in terms of sensitivity and specificity with the most commonly used tests for camel brucellosis. The results of the present study are of paramount importance for designing surveillance and control measures for brucellosis in camel populations.

Keywords: brucellosis diagnosis; dromedary camels; performance; serological tests.