Resistance of Salmonella serotypes to chloramphenicol

Area of Science:

• Microbiology
• Infectious Diseases
• Antimicrobial Resistance

Background:

• Chloramphenicol is a broad-spectrum antibiotic used to treat bacterial infections.
• Monitoring antimicrobial resistance in bacterial pathogens like Salmonella is crucial for public health.
• Salmonella strains can develop resistance to antibiotics, posing treatment challenges.

Purpose of the Study:

• To assess the current chloramphenicol resistance patterns in Salmonella strains isolated from various sources in India.
• To determine if antimicrobial resistance to chloramphenicol has increased over time in these strains.

Main Methods:

• Testing 704 Salmonella strains from diverse origins for their susceptibility to chloramphenicol.
• Evaluating resistance at varying chloramphenicol concentrations (up to 10 µg/ml).
• Analyzing resistance profiles across different Salmonella serotypes and isolation sources.

Main Results:

• 95.4% (671/704) of Salmonella strains were sensitive to chloramphenicol at 10 µg/ml.
• The majority of sensitive strains showed susceptibility at lower concentrations (2-4 µg/ml).
• No chloramphenicol-resistant Salmonella strains were identified in isolates from animals, including poultry.

Conclusions:

• Salmonella strains in India exhibit a high degree of sensitivity to chloramphenicol.
• There is no evidence of increased chloramphenicol resistance in Indian Salmonella strains over the study period.
• The findings suggest that chloramphenicol remains an effective treatment option for Salmonella infections in the region, unlike potential trends elsewhere.