Prevalence of SCC mec Type IV in Nosocomial Bloodstream Isolates of Methicillin-Resistant Staphylococcus aureus

Abstract

Over a period of 7 months, 151 consecutive methicillin-resistant Staphylococcus aureus blood isolates were evaluated. None was community acquired. Twenty (13%) were susceptible to four or more antimicrobials, and 95% of these isolates were identified as SCCmec type IV. Molecular typing demonstrated four patterns, with one predominant pattern. Although usually community acquired, SCCmec type IV in our setting is clearly nosocomial.

Type IV SCCmec found in decade old Brazilian MRSA isolates

“…The finding of strains carrying a type IV SCCmec in the present study among strains isolated at least 7 years ago, and moreover the report of a recent outbreak of type IV SCCmec strains at a Brazilian university hospital, reported by Trindade et al [31], indicates that clones bearing a type IV SCCmec have been present in Brazil for quite some time, and must have escaped undetected. These strains are disseminating in hospitals where they may be adapting to vanquish the intense antimicrobial selective pressure present in a nosocomial environment.…”

New multilocus sequence typing of MRSA in São Paulo, Brazil

“…The predominance of BEC (SCCmec III) in Brazilian hospitals has been well documented (3,4,14). Recent changes in the profile of clonal MRSA isolated in hospitals have been observed, which have increased the number of MRSA isolates belonging to SCCmec type IV (pediatric clone), as shown in the study by Trindade et al (15), who reported a 13% rate of occurrence of MRSA isolates in patients carrying this SCCmec admitted to a São Paulo hospital.…”

“…Pediatric clone samples seem to be associated with nosocomial infections in other Brazilian cities like Rio de Janeiro, Recife, and in Rio Grande do Sul (14) and São Paulo (15). More studies are needed to characterize MRSA clones not belonging to BEC in Brazil genotypically.…”

The occurrence and dissemination of methicillin and vancomycin-resistant Staphylococcus in samples from patients and health professionals of a university hospital in Recife, State of Pernambuco, Brazil

“…These percentages may be considered low, as the prevalence of isolation of MRSA strains ranges from 40 to 80% 2,9,24 in Brazilian hospitals, and the data from the Antimicrobial Surveillance Program (SENTRY) show that MRSA corresponds to 31% of the causes of nosocomial and community infections and is considered the most common among the most prevalent pathogens 25 . However, the fact that professionals have a higher percentage of MRSA points to contamination in the hospital itself.…”