Abstract

Background: Salmonella is one of the leading causes of foodborne illness in Malawi. The dissemination of drug-resistant strains through the food chain has important implications for the treatment failure of salmonellosis in human medicine. This study investigated the prevalence and antimicrobial resistance patterns of zoonotic Salmonella strains associated with poultry. Methods: Samples of chicken droppings from commercial poultry farms within the Mphate area of Ntcheu District in Malawi were collected using a multi-stage sampling technique followed by pooling. Salmonella Shigella agar and Brilliant Green agar were used to isolate the targeted zoonotic species. This was followed by the classification of isolated species using the Analytical Profile Index 20E system and an antimicrobial susceptibility test to establish their antimicrobial resistance pattern. Results: Salmonella species were found in 6 out of 12 samples, with 41.6% (5) belonging to the Non-Typhoidal Salmonella group. S. typhimurium was the most isolated serovar (60%, n=3), followed by S. enteriditis (20%, n=1) and S. enterica subgroup 1 (20%, n=1). The study revealed that chicken droppings harbor Salmonella serovars resistant to common antibiotics, which is a public health issue. The most significant resistance was observed against against Tetracycline (100%), Sulfamethoxazole (80%), Ceftazidime (60%), Gentamicin (40%), Ciprofloxacin (40%) and Ampicillin (20%). Further analysis showed that Salmonella var. typhimurium DT 104 exhibited the highest antibiotic resistance (n=6, 100%), followed by Salmonella var. typhimurium strain 2 (n=5, 83%) and Salmonella var. enterica sub-group 1 (n=3, 50%). All strains that showed resistance against more than two antibiotics were found in layer chickens, with all isolates being resistant to at least one antibiotic. Conclusion: The findings revealed that poultry in Ntcheu District harbours several multidrug-resistant zoonotic strains of Salmonella. There is therefore a

Pages (from-to)	15-23
Volume	7
Issue number	02
Publication status	Published - 2025