One health approach based descriptive study on Coxiella burnetii infections in camels and abattoir workers in the United Arab Emirates

Coxiellosis is a zoonotic bacterial disease caused by Coxiella burnetii (C. burnetii) infection that occurs as subclinical and clinical infections in animals and humans worldwide except in the Antarctica and New Zealand. The objectives of this study were to estimate the seroprevalences of C. burnetti infections in slaughtered camels and abattoir workers as well as to detect C. burnetii DNA in the clotted blood in the same study subjects at Al Bawadi abattoir of Al Ain city, in the United Arab Emirates, UAE. A cross-sectional study design was used to test 393 slaughtered camels and 86 abattoir workers for C. burnetii antibodies between March 2022 and July 2023 using enzyme-linked immunosorbent assay (ELISA) kits supplied by ID Vet multispecies and Abbexa, respectively. Besides, real-time polymerase chain reaction (qPCR) was used for the detection of C. burnetti DNA in clotted blood of 366 camels and 86 abattoir workers. The seroprevalences of C. burnetii infection were 52.9% (95% confidence interval, CI: 46.0, 60.6%) and 24.4% (95% CI: 15.1, 37.3%) in camels and abattoir workers. But, C. burnetii DNA was not detected in clotted blood samples of camels and abattoir workers. Sex, age and body condition of the camels were not associated with the seroprevalence of C. burnetii while abattoir workers of African origin were more likely to be seropositive (odds ratio, OR = 3.70; 95% CI: 1.05, 13.60) than abattoir workers of south Asian origin. The seroprevalences of C. burnetii infections were high in both slaughtered camels and abattoir workers although its DNA was not detected in the clotted blood of either of the study subjects.