In this study, the HA-MRSA
isolates were more likely to contain the tetM (91.6% versus 69.9%), tetK (45.8% versus 19.2%) and tetL (11.2% versus 9.6%) genes and less likely to contain tetO (15.0% versus 30.1%) than the HA-MSSA isolates.
Both CA-MRSA and HA-MRSA
are resistant to traditional anti-staphylococcal beta-lactam antibiotics.
Although most USA300 and USA400 isolates are currently resistant to fewer classes of antimicrobial drugs than are HA-MRSA
isolates (13), a recent paper by Han et al.
Hospital-acquired MRSA and community-acquired MRSA have sometimes been used synonymously with the terms HA-MRSA
Nevertheless, CA-MRSA isolates are increasingly being reported as pathogens in the general population in persons with no risk factors for HA-MRSA
In the USA, HA-MRSA
clones are rapidly being replaced by CA-MRSA clones.
During the 1990s, MRSA emerged as a cause of infection among healthy persons in the community who had none of the above HA-MRSA
risk factors (5-10).
Most CA-MRSA remained susceptible to many antimicrobial drugs, but genetic exchange between strains resulting in acquisition of resistance determinants in CA-MRSA or transfer of virulence markers into HA-MRSA
are important concerns.
At the moment, the restriction between CA-MRSA and HA-MRSA
is beginning to fade.
Thirty-seven of the HA-MRSA
isolates were considered Danish nosocomial isolates (domestic HA-MRSA
), and 5 were from patients transferred from foreign hospitals (imported HA-MRSA
For all 19 HA-MRSA
isolates, seven different clones (>80% similarity) were found (A-G) to be related to CC5 (53%; 10/19) and CC45 (47%; 9/19) and nine spa types were characterized.
Cases were classified as HA-MRSA
or other MRSA (Table 1).