ABSTRACT
The geographical distribution of 65 clinical isolates of methicillin resistant Staphylococcus aureus (MRSA) recovered from 7 hospitals in Thailand was investigated. The presence of mecA gene in MRSA was determined by specific PCR with the use of primers 5'-GTAGTTGTCGGGTTTGGT-3' and 5'-GGTATCATCTTGTACCCA-3'. Chromosomal DNA restriction analysis with SmaI was resolved by pulsed-field gel electrophoresis (PFGE) compared with antibiotype analysis and phage type analysis. All 65 strains carried mecA gene. They all were resistant to penicillin, tetracycline, erythromycin, amoxicillin/clavulanic acid and variably resistant to gentamicin, ofloxacin, trimethoprim-sulfamethoxazole, chloramphenicol, fosfomycin and clindamycin; and all isolates were susceptible to vancomycin. A total of 19 PFGE patterns designated as type A, A1, A2, A3, A4, B, B1, C, D, E, E1, E2, F, F1, F2, G, H, I and J was identified. Type A4 and E were commonly found in every studied areas. Phage typing showed even greater variability that 52 (80%) isolates belonged to 25 different phage types; 13 (20%) isolates were non-typable. The clarity and polymorphism of the PFGE patterns enable us to discriminate between isolates which could not be differentiated by antibiogram or phage type analysis. The findings demonstrate the existence of a common epidemic MRSA clone in Thailand.
Subject(s)
Bacterial Typing Techniques , Bacteriophage Typing , Cross Infection/epidemiology , Drug Resistance, Microbial , Drug Resistance, Multiple , Electrophoresis, Gel, Pulsed-Field , Genes, Bacterial , Humans , Methicillin Resistance , Microbial Sensitivity Tests , Staphylococcal Infections/epidemiology , Staphylococcus aureus/classification , Thailand/epidemiologyABSTRACT
Legionellae was found in 57 per cent of 94 cooling towers and 21.8 per cent of 78 other environmental sources. These figures reveal that the existence of legionellae in cooling towers is more prevalent than that found in other environmental sources. Legionella pneumophila serogroup 1 was the most prevalent organism among the legionellae found in cooling towers and other environmental sources. The recovery of legionellae in each province was seasonally independent and was found throughout the year. This is the first report of an environmental survey representing the existence of legionellae in every region of Thailand.