Diversity and antimicrobial drug resistance of non-typhoid Salmonella serotypes isolated in lettuce, irrigation water and clinical samples in Burkina Faso

Introduction: The contamination of fresh vegetables by non-typhoid Salmonella species present in irrigation water and animal feces could causes of many diarrheal infections and diseases. The aim of this study was to determine the diversity of non-typhoidal Salmonella serotypes and their antimicrobial resistance profile from lettuce, irrigation water and human samples. Methods: This study concern 57 Salmonella isolated from 134 lettuce and irrigation water samples and 416 stool samples. All Salmonella isolated were characterized used serotyping antisera according to Kauffman-White-Le Minor scheme. Salmonella strains were characterized by simplex PCR using specific primers. Results: Out of 57 Salmonella isolated, (42/134) 31.34% were from lettuce and irrigation water and (15/416) 03.6% from human. A total of 36 different serotypes were identified. Highest prevalence was obtained with S. Cubana, S. Jodhpur and S. Kentucky 05/57 (08.77% each) followed by S. Poona 04/57 (07%). Resistance genes CTX-M1, aadA1, dfrAI, were obtained with S. Jodhpur and CTX-M2, aac(3-Id), aadA7 with S. Kentucky. However, resistance genes gyrA, gyrB and parE were found in S. Essen, S. Poona and S. Senftenberg. Virulence gene such as invA, pipD and misL were found in 91% globally, followed by orfL 81% and spvR 12%. Conclusion: This study highlighted the diversity of non-typhoid Salmonella serotypes and resistance genes circulating in environment and hospital center in BF. Gardening products should be a potential source of transmission of Salmonella causing diarrhea among human in BF. Microbiological and antimicrobial resistance plans must be implemented so that they are tools for infection prevention.

Automated summary

This study identified a variety of non-typhoidal Salmonella serotypes and resistance genes in lettuce, irrigation water, and human samples. Some strains showed antibiotic resistance, posing a risk for transmission to humans. Efforts to prevent infection should include microbiological and antimicrobial resistance plans.