Vol. 12, Special Issue 12 (2023)

Author(s):
Vivek K Naik, Sanjay Shakya, Anil Patyal, SL Ali, Subhash K Verma, SD Hirpurkar, Mamta Choudhary and Abhinav Verma

Abstract:
Small ruminants, predominantly owned by impoverished farmers in India, serve as significant reservoirs for zoonotic pathogens, demanding a thorough understanding of prevalence. In India, where bovine brucellosis is endemic, sheep and goats are identified as major sources of infection, mirroring clinical manifestations of B. melitensis in small ruminants and B. abortus in cattle. The risk of human infection arises from contact with infected materials or consumption of contaminated raw milk. PCR, particularly AMOS PCR, is crucial for diagnosing Brucella spp., but the lack of epidemiological data hinders effective control. The study, using a risk factor questionnaire and an integrated approach, provides valuable insights for developing intervention programs and policies in Chhattisgarh, India. The cross-sectional study in Chhattisgarh (February 2022 to March 2023) involved obtaining blood samples from 750 small ruminants and additional clinical samples. DNA extraction, PCR techniques, and gel electrophoresis were utilized for molecular detection of Brucella spp., targeting Bcsp31 and AMOS PCR for genus and species confirmation. A risk factor questionnaire assessed farming practices, rearing conditions, and contact, contributing to a comprehensive understanding. Statistical analyses involved Chi- square (χ²) statistics with Fisher’s exact test, univariable logistic regressions, and mixed-effects multivariable logistic regression models to identify risk factors for Brucella positivity. The study conducted in Chhattisgarh revealed a 2.26% prevalence of Brucella spp., with blood samples showing 1.87% prevalence. Notably, goats had 2.1% prevalence, while sheep exhibited a higher prevalence of 5.13%, and males showed a significantly higher prevalence (4.17%) compared to females (1.87%). Among various risk factors, animals aged 2.5 years had the highest prevalence (6.14%), and the number of small ruminants was identified as a significant predictor of Brucella spp. infection at the farm level (OR: 1.103, 95% CI: 1.032-1.178). Additionally, a history of reproductive disorder was significantly associated with a lower odds ratio of Brucella spp. infection (OR: 0.040, 95% CI: 0.002-0.836), while the introduction of new animals and proper disposal of placenta did not reach statistical significance in this analysis. These findings contribute to our understanding of Brucella spp. epidemiology in Chhattisgarh and provide a foundation for tailored strategies to mitigate transmission risks and safeguard both animal and public health.