ABSTRACT
UNLABELLED: TARGET OF THE STUDY: Strain typing of pathogens is essential to pinpoint the sources and routes of transmission and to forecast future trends. In a general hospital, we studied possible changes in the MRSA population. PATIENTS AND METHODS: MRSA isolates received from a Belgian general hospital, during 2002 (n=150) and the second half of 2007 (n=105), were compared by phage and spa typing. RESULTS: In 2002, [J]* phage types characterized 45% of the MRSA isolates, 13% belonged to the [O]* phage types, 12% to a local phage type 29/42E/54/D11* and 28% were not assigned to a defined group. Thirteen different spa types were found among the isolates: 39% belonged to t038, 27% to t121, 14% to t041, 5% to t740, and 4% to t002 and t024 each. Two spa types were found respectively in two and three isolates, five were unique. In 2007, 35% belonged to [J]*, 23% to [O]* and 39% could not be put in a defined group. Eighteen different spa types were found: 30% belonged to t740, 29% to t121, 13% to t038 and 10% to t002. Three spa types were represented in two isolates, eleven were unique. The t041 spa type was specific for the 29/42E/54/D11* and the majority of the t121 isolates were related to [J]*. CONCLUSION: [J]* remained the dominant phage types group but decreased whereas [O]*, the second phage types group, increased. As to the spa types, t740 became dominant while t121 remained second. Phage and spa typing point to some quantitative changes among the Belgian MRSA population.
Subject(s)
Bacterial Typing Techniques/methods , Bacteriophage Typing/statistics & numerical data , Cross Infection/microbiology , Methicillin-Resistant Staphylococcus aureus/classification , Staphylococcal Infections/microbiology , Staphylococcal Protein A/analysis , Aged , Aged, 80 and over , Bacterial Typing Techniques/statistics & numerical data , Belgium/epidemiology , Cross Infection/epidemiology , DNA, Bacterial/genetics , Female , Hospitals, General/statistics & numerical data , Humans , Male , Methicillin-Resistant Staphylococcus aureus/isolation & purification , Middle Aged , Retrospective Studies , Staphylococcal Infections/epidemiology , Staphylococcal Protein A/genetics , Staphylococcus Phages/isolation & purificationABSTRACT
Between 1998 and 2003, 5,161 isolates (3,182 human) of Salmonella enterica were received by the National Salmonella Reference Laboratory of Ireland. Serotyping, antimicrobial susceptibility testing and phage typing were performed by standard methods. The number of isolates of S. enterica serovar Typhimurium decreased from 579 (80%) in 1998 to 208 (19%) in 2003, while S. enterica serovar Enteritidis increased from 59 (8%) in 1998 to 219 (20%) in 2003. Definitive (DT) phage types 104 and DT104b accounted for a declining proportion of all Salmonella Typhimurium isolates (from n = 523 [90%] in 1998 to 126 [60%] in 2003). Numbers of Salmonella Enteritidis phage type 4 declined from 50 (85%) in 1998 to 59 (27%) in 2003. Twenty-eight isolates of typhoidal Salmonella were received with a history of recent travel in 17 cases. Resistance to multiple (four or more) antimicrobial agents was related to serotype and, where applicable, phage type, and was common in Salmonella Typhimurium. Salmonella Typhimurium predominated among isolates from cattle and pigs (n = 213 [58%]), while Salmonella Livingstone (n = 327) and S. Kentucky (n = 227) were predominant in isolates from poultry (total n = 554 [43%]). This paper discusses trends, and their implications, in Irish salmonella isolates since the establishment of the Reference Laboratory.
Subject(s)
Anti-Bacterial Agents/pharmacology , Bacteriophage Typing/statistics & numerical data , Disease Outbreaks , Drug Resistance, Bacterial , Salmonella enterica , Salmonella typhimurium/classification , Serotyping/statistics & numerical data , Animals , Bacteriophage Typing/methods , Humans , Ireland/epidemiology , Salmonella enterica/classification , Salmonella enterica/drug effects , Salmonella enterica/isolation & purification , Salmonella typhimurium/isolation & purification , Species Specificity , TravelABSTRACT
Salmonella Enteritidis strains are the most often isolated Salmonella serovar in Poland. In the present study, phage typing, antibiotic resistance testing and plasmid profile analysis, have been applied to characterise 41 Polish S. Enteritidis isolates originated from human cases of salmonellosis and from other sources. The typing phages of Ward and colleagues scheme were used to type a total of 41 S. Enteritidis strains coming from Poland. All 41 strains were typable and 5 different phage types were observed. Among 41 strains tested, both PT6 and PT21 were recognized in the 15 strains (36.6%). Nine strains (22%) belonged to phage type 8. The others PTs were represented by small amount of strains (PT1var and PT4). Among all tested isolates only 4 different plasmid profiles were observed. Of the 41 strains investigated, 16 (39%) contained the 57 kb plasmid alone. The remaining 25 strains (61%) except 57 kb plasmid, possessed additional DNA particles. The probable phage type conversion of PT21 to PT1var strain, possibly connected with smaller DNA particle presence, was observed. This hypothesis needs confirmation. The real S. Enteritidis epidemiological situation in Poland should be known after introducing of systematic, annual research program.
