Seroepidemiology of caprine Brucellosis in Jordan

The seroprevalence and risk factors for Brucella seropositivity in goats in Jordan were investigated. Serum samples were collected from 1100 goats randomly from 69 herds. The rose bengal plate test and the complement fixation test were used to detect antibodies against Brucella. A structured questionnaire was used to collect information on goat health and management. Questionnaire information was tested in a multivariable logistic regression model to identify risk factors for Brucella seropositivity. In addition, the incidence of Brucella-specific abortion was investigated in goat herds located in the northern part of Jordan. Of the 1100 goats sampled, 305 (27.7%) had antibodies against Brucella. Thirty-seven herds (53.6%) had at least one Brucella seropositive goat. The prevalence of brucellosis in goats was significantly higher (P < 0.01) in the southern part of Jordan than that in central or northern Jordan. The multivariable logistic regression model identified large herds (OD = 2.6; 95% CI: 2.1, 2.9), not using disinfectants (OD = 2.8; 95% CI: 2.1, 3.8), not vaccinating with Rev 1 vaccine (OD = 1.7; 95% CI: 1.1, 3.0) and contact with other goat herds (OD = 1.8; 95% CI: 1.3, 2.7) as risk factors for Brucella-seropositivity. The incidence of Brucella-caused abortion was 27% (95% CI: 19, 32). Most of the isolated Brucella strains from the aborted fetuses and vaginal swabs were characterized as Brucella melitensis biotype 1. Brucella abortus biotype 9 was isolated from only one aborted fetus.