ABSTRACT
Salmonella enterica is frequently associated with outbreaks of human salmonellosis, and products of avian origin, such as eggs and chicken meat, are the main vehicles of its transmission. The present study describes the occurrence of different serovars of Salmonella enterica and phagotypes of S. enterica serovar Enteritidis in eggs destined for human consumption. Four thousand eggs obtained from commercial egg laying farms and one thousand discarded hatching eggs from broiler farms, which were acquired at farmers' markets and informal shops, were analyzed. Salmonella spp. was isolated from 52.0% of the discarded hatching eggs, in which the predominant serovar was Enteritidis (84.6%), and the predominant Salmonella Enteritidis phagotype (PT) was PT7 (26.9%). Salmonella spp. was not isolated from eggs obtained from commercial egg laying farms. The antimicrobial resistance profile showed that 23.1% (n = 6) of the SE strains were resistant to nalidixic acid. The results suggest that the consumption of discarded hatching eggs represents an important source of Salmonella transmission to humans.
Subject(s)
Eggs/microbiology , Salmonella/classification , Salmonella/isolation & purification , Animals , Anti-Bacterial Agents/pharmacology , Chickens , Drug Resistance, Bacterial , Humans , Prevalence , Salmonella/drug effects , SerogroupABSTRACT
Salmonella enterica is frequently associated with outbreaks of human salmonellosis, and products of avian origin, such as eggs and chicken meat, are the main vehicles of its transmission. The present study describes the occurrence of different serovars of Salmonella enterica and phagotypes of S. enterica serovar Enteritidis in eggs destined for human consumption. Four thousand eggs obtained from commercial egg laying farms and one thousand discarded hatching eggs from broiler farms, which were acquired at farmers' markets and informal shops, were analyzed. Salmonella spp. was isolated from 52.0% of the discarded hatching eggs, in which the predominant serovar was Enteritidis (84.6%), and the predominant Salmonella Enteritidis phagotype (PT) was PT7 (26.9%). Salmonella spp. was not isolated from eggs obtained from commercial egg laying farms. The antimicrobial resistance profile showed that 23.1% (n = 6) of the SE strains were resistant to nalidixic acid. The results suggest that the consumption of discarded hatching eggs represents an important source of Salmonella transmission to humans.
Subject(s)
Animals , Humans , Eggs/microbiology , Salmonella/classification , Salmonella/isolation & purification , Anti-Bacterial Agents/pharmacology , Chickens , Drug Resistance, Bacterial , Prevalence , Serogroup , Salmonella/drug effectsABSTRACT
A total of 41 Salmonella Enteritidis strains, including phago-types (PTs) PT4 and PT9, were characterized by antimicrobial resistance profiles and PFGE. Of these strains, 34 were isolated from patients and foods, and 7 were of poultry origin. All strains were susceptible to ampicillin, chloramphenicol, cefotaxime, ciprofloxacin and trimethoprim/sulfamethoxazole, and 41.5â% (nâ=â17) were resistant to nalidixic acid. PFGE analysis using XbaI and SpeI restriction enzymes resulted in X1S1 as the prevalent pattern, which was present in 48.8â% (nâ=â20) of epidemic strains and in one strain isolated from discarded hatching eggs. Distinct patterns were found for the other strains isolated from poultry (X3S1, X8S8, X11S12, X11S13, X16S1 and X13S15). The S. Enteritidis PT9 strains associated with outbreaks of salmonellosis were highly similar (≥0.90), suggesting clonality. The PFGE genotypes were related to the PTs, and it was possible to differentiate strains isolated from patients with salmonellosis from other strains of non-epidemic origin. The PFGE results suggested that the S. Enteritidis strains of poultry origin were a possible source of human salmonellosis during the study period.
Subject(s)
Anti-Bacterial Agents/pharmacology , Drug Resistance, Multiple, Bacterial/genetics , Salmonella Infections/microbiology , Salmonella enteritidis/drug effects , Salmonella enteritidis/genetics , Brazil/epidemiology , Disease Outbreaks , Electrophoresis, Gel, Pulsed-Field , Humans , Phylogeny , Salmonella Infections/epidemiology , Salmonella enteritidis/classificationABSTRACT
The antimicrobial susceptibility of 212 Salmonella strains isolated from patients and foods was evaluated and 45 percent were found to be resistant to nalidixic acid. Nalidixic acid resistant strains showed a higher minimal inhibitory concentration for ciprofloxacin than sensitive strains. During the study an increase of strains with reduced susceptibility to ciprofloxacin was also observed.
Subject(s)
Humans , Nalidixic Acid/analysis , Nalidixic Acid/isolation & purification , Ciprofloxacin/analysis , Disease Susceptibility , Drug Resistance, Microbial , Fluoroquinolones , Quinolones , Salmonella Infections , Salmonella/growth & development , Salmonella/isolation & purification , Food Samples , Microbial Sensitivity Tests , Patients , MethodsABSTRACT
The antimicrobial susceptibility of 212 Salmonella strains isolated from patients and foods was evaluated and 45% were found to be resistant to nalidixic acid. Nalidixic acid resistant strains showed a higher minimal inhibitory concentration for ciprofloxacin than sensitive strains. During the study an increase of strains with reduced susceptibility to ciprofloxacin was also observed.
