Seroprevalence and Associated Risk Factors of Bovine Brucellosis in District Gujranwala, Punjab, Pakistan

SIMPLE SUMMARY: Our study estimated the seroprevalence of brucellosis in bovine herds and identified the important risk factors associated with the occurrence of the disease at livestock farms. A total of 220 sera from 46 bovine herds of district Gujranwala, Punjab, Pakistan, was collected and subjected to brucellosis screening by serology. It resulted in 58.7% herd-based and 22.7% individual animal-based seroprevalence. Age, herd size and previous history of abortion came out as associated risk factors. Strict biosecurity, personal protection, quarantine measures and routine screening are recommended at livestock-holdings/farms, whereas disease awareness and pasteurization of milk are recommended for the general population to prevent zoonosis. ABSTRACT: Bovine brucellosis is a contagious zoonotic disease that causes economic losses through abortion and infertility. A cross-sectional study was designed to determine the seroprevalence and associated risk factors of bovine brucellosis in district Gujranwala of Punjab, Pakistan. A total of 220 bovine sera (112 from buffaloes, 108 from cattle) from 46 unvaccinated herds were collected. Parallel testing by the Rose Bengal Plate Test (RBPT) and Indirect Enzyme-linked Immunosorbent Assay (I-ELISA) showed a 58.7% (27/46) herd-level and 22.7% (50/220) animal-level seroprevalence. Seroprevalence was higher (p < 0.001, OR = 7.62) in adult animals (37.2%) compared to younger animals (4.9%). A herd size of >10 animals (p = 0.021, OR = 7.83), less housing space (p = 0.037, OR = 6.39) and history of abortion at the farm (p = 0.023, OR = 5.6) were found as risk factors associated with the seropositivity of brucellosis. There was a substantial agreement between the RBPT and I-ELISA results (Cohen’s kappa coefficient (κ) = 64.16, percent agreement = 89.5%). In conclusion, a relatively higher seroprevalence was found compared to the previous reports from the country. Standardization and validation of the advanced diagnostic tests would be needed. Biosecurity, personal protection, quarantine measures and routine screening of animals at the farm level and disease awareness programs and consumption of pasteurized milk in the human population will be helpful in preventing the transmission/zoonosis of the disease.