Total bacteria load, selected pathogens (vibrio spp., EHEC, salmonella spp. and shigella spp.) and their antibiotic susceptibility patterns from bio-slurry of selected biodigesters in Wakiso District, Uganda

Background The utilization of bio-slurry as a nutrient-rich organic fertilizer in sustainable agricultural practices has gained significant attention. However, the presence of pathogenic bacteria in bio-slurry poses a potential risk to human health and the environment. This study aimed at understanding the total bacteria load, prevalence of selected pathogens ( Vibrio , EHEC, Salmonella , and Shigella ), and their antibiotic susceptibility patterns, including multi-drug resistance, for assessing the safety and effectiveness of bio-slurry application in agriculture. A cross-sectional study was conducted in Wakiso District with a total of 40 samples collected from 12 villages, representing different biodigesters with various feedstock materials, including cow dung, poultry fecal products, pig and rabbit urine. The collected samples were analyzed to determine the distribution of materials used in the biodigesters, the prevalence and distribution of selected bacterial pathogens ( Shigella Salmonella, Vibrio spp and Enteroheamarrhic Ecoli strains). The antimicrobial susceptibility patterns of isolated bacterial pathogens were assessed using the disk diffusion method, testing multiple commonly used antibiotics to identify multi-drug resistance among the bacterial isolates. Results The prevalence of selected pathogens revealed Enteroheamorrhagic Escherichia coli (EHEC) as the most prevalent pathogen (31%), followed by Shigella spp. and Vibrio spp, all at (25%) while Salomenella spp were the least prevalent (19.0%). The isolated bacterial pathogens showed varying levels of resistance against different antibiotics with EHEC displaying high resistance to Amoxicillin and moderate resistance to Ciprofloxacin. Salmonella spp demonstrated high resistance to Amoxicillin and moderate resistance to Azithromycin and Ampicillin, highlighting potential Multi-Drug Resistance concerns. Conclusions The distribution of selected pathogens highlighted the importance of implementing stringent safety protocols during bio-slurry handling and management to mitigate potential health risks. Moreover, prudent antibiotic use in animal production systems is essential in addressing Multi-Drug Resistance in bacterial pathogens found in bio-slurry. Further research on treatment technologies and potential risks associated with bio-slurry application is recommended to develop efficient and safe strategies for bio-slurry management in agriculture.