Seroprevalence Rate of Brucellosis in Sheep at Aljouf Region, Saudi Arabia

Abstract

In this work, the prevalence of Brucella spp. antibodies among sheep in Aljouf region, Saudi Arabia was investigated. Five hundred and fifty sera were collected randomly during March to April 2021 from sheep of both sexes, age and breed in the region. Samples were tested for circulating antibodies against Brucella spp. by Rose Bengal Plate Test (RBPT), Rapid test (RT) and ELISA. Pearson's Chi-square was adopted to estimate possible correlation between RBPT, Rapid test, ELISA and risk factors involved. Kappa test was used to measure agreement of the results and the tests adopted. Out of the tested sera forty (7.3%) were positive for Brucella spp. antibodies by RBPT, 23 (18.4%) in Dumataljundal, 16 (16.7%) among male, compare to 24 (5.3%) among female, 28 (70%) were positive among the groups of 12-30 month age. On the other hand, eighty-eight (16%) sera were positive in Brucella ssp. Antibodies by rapid test, 39 (31.2%) in Dumataljundal, 23 (24.0%) among male, compared to 65 (14.3%) in female, higher percentage (20.7%) of antibodies was found in 36-48 months old. ELISA revealed that eighty-five samples (15.5%) were positive by ELISA, 39 (31.2%) in Dumataljundal, 23 (24%) among male, compared to 62 (13.7%) in female, higher percentage (19.8%) of Burucella spp. antibodies was found in 36-48 month age. Significant correlation between seroprevalence screened by RBPT and city (-0.168), sex (-0.166) and age (0.121) were recorded. Likewise, significant relationship between seropositivity detected by rapid test and city (-0.311), sex (-0.100) and age (0.088) were estimated. ELISA results were correlated with city (-0.297), sex (-0.108) and age (0.085). Analysis revealed strong correlation between ELISA and rapid test (0.980), moderate correlation (0.636) between ELISA and RBPT was noticed. Kappa test indicated moderate agreement between RBPT and ELISA (value=.583), while perfect agreement between rapid test and ELISA was estimated (value=.979). Large-scale epidemiological investigation is needed to better understand possible risk factors involved and to implement effective control measures.

Seroprevalence and Identification of Brucella melitensis Based on a Glycosyltransferase Gene among Ruminants in Rafha, Saudi Arabia

“…Sex wise, seroprevalence was comparable to the previous reports. 15,52 But it differs with other literature. 34,53,54 Difference may be due to the immune response or the interaction of other risk factors.…”

“…7,8,26 Much higher seroprevalence (31.7%) was reported at Duhok in northern Iraq. 27 However, it was slightly higher than the reported one (7.3%) in Aljouf region, Saudi Arabia, 15 and in Aseer and Jazan (5.1%) in southern Saudi Arabia, 28 also that found (8.3%) in India. 29 Nevertheless, none of tested sheep sera in Farasan Islands in the Red Sea in southwestern Saudi Arabia were found to be positive.…”

“…Age-level showed that was higher in adult animals, it's supported by previous research. 15,40 It may be owing to sex hormones, which may stimulate the growth of the bacteria, and tend to increase in concentration with age and sexual maturity. This might be true since older animals keep on in the flock for a long time, and they had a longer duration of contact.…”

“…[6][7][8] It is regarded as a main public health and agricultural problem in the country. [9][10][11][12][13][14][15] The RBT is an affordable, quick, simple and efficient screening and a diagnostic test for individual animals and herds. 7,16 To adopt effective control measures, large-scale epidemiological studies are required.…”