A common Salmonella Enteritidis sequence type from poultry and human gastroenteritis in Ibagué, Colombia

Abstract

Introduction: Salmonella Enteritidis is a major cause of human salmonellosis in the world being the contaminated eggs and raw chicken meat as the principal route of infection. In Ibagué, Colombia, the main serovars of Salmonella spp. circulating in laying hen farms, surface of eggs and in raw chicken carcasses were identified, however, whether those serovars are responsible for gastroenteritis is currently unknown. Objective: To evaluate the genetic relationship between Salmonella Enteritidis isolates from poultry and those from humans with gastroenteritis using multilocus sequence typing (MLST). Materials and methods: Salmonella spp., was isolated from clinical cases of gastroenteritis (n=110). Antibiotic susceptibility tests, followed by serotyping and MLST were conducted and S. Enteritidis was compared to those from laying hen farms and marketed eggs. Results: Ten isolates of Salmonella spp., were obtained from stools of people with gastroenteritis. The prevalence of Salmonella spp., in human stools was 9.09 % and S. Enteritidis (n=4), S. Typhymurium (n=2), S. Newport (n=1), S. Uganda (n=1), S. Grupensis (n=1), and S. Braenderup (n=1) were the main serotypes. MLST indicated that a common S. Enteritidis sequence type (ST11) was present in all three sources and showed the same antibiotic resistant pattern. Conclusion: S. Enteritidis ST11 constitutes a link between consumption/manipulation of contaminated eggs and human gastroenteritis in Ibagué. Additional studies are needed to know whether other Salmonella serovars isolated from raw chicken meat also associate with human gastroenteritis.