Related Experiment Video
Updated: Jun 11, 2025
Subcutaneous Infection of Methicillin Resistant Staphylococcus Aureus MRSA
Published on: February 9, 2011
ST105 Lineage of MRSA: An Emerging Implication for Bloodstream Infection in the American and European Continents
Alice Slotfeldt Viana1, Laís Pires do Valle Tótola1, Agnes Marie Sá Figueiredo1,2
1Departamento de Microbiologia Médica, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-902, Brazil.
Abstract:
Sequence-type 5 (ST5) of methicillin-resistant Staphylococcus aureus (MRSA), harboring the staphylococcal chromosomal cassette mec type IV (SCCmecIV), was first detected in Portugal. It emerged as a significant cause of healthcare-associated (HA) infection in pediatric units and was hence named the pediatric clone. Another ST5 lineage, which carries SCCmecII, also prevailed in the USA and Japan for multiple years. More recently, another MRSA lineage, ST105-SCCmecII, part of the evolution of clonal complex 5 (CC5) MRSA, has emerged as the cause of hospital-acquired bloodstream infection outbreaks in countries including Portugal, the USA, and Brazil. This article reviews studies on the epidemiology and evolution of these newly emerging pathogens. To this end, a search of PUBMED from inception to 2024 was performed to find articles reporting the occurrence of ST105 MRSA in epidemiologic studies. A second search was performed to find studies on MRSA, CC5, ST5, and SCCmecII. A search of PUBMED from 1999 to 2024 was also performed to identify studies on the genomics and evolution of ST5, CC5, and ST105 MRSA. Further studies were identified by analyzing the references of the previously selected articles from PUBMED. Most articles on ST105 MRSA were included in this review. Only articles written in English were included. Furthermore, only studies that used a reliable genotyping method (e.g., whole genome sequencing, or MLST) to classify the CC5 lineages were selected. The quality and selection of articles were based on the consensus assessment of the three authors in independent evaluations. In conclusion, ST105-SCCmecII is an emerging MRSA in several countries, being the second/third most important CC5 lineage, with a relatively high frequency in bloodstream infections. Of concern is the increased mortality from BSI in patients older than 15 years and the higher prevalence of ST105-SCCmecII in the blood of patients older than 60 years reported in some studies.
Insights
Methicillin-resistant Staphylococcus aureus (MRSA) ST105-SCCmecII is an emerging pathogen causing bloodstream infections globally. This lineage shows increased mortality in older patients, highlighting its public health significance.
Area of Science:
- Microbiology
- Infectious Diseases
- Epidemiology
Background:
- Sequence-type 5 (ST5) of methicillin-resistant Staphylococcus aureus (MRSA) is a significant cause of healthcare-associated infections.
- Different ST5 lineages, such as ST5-SCCmecIV and ST5-SCCmecII, have emerged globally, with varying epidemiological impacts.
- ST105-SCCmecII represents a recently identified MRSA lineage within clonal complex 5 (CC5).
Purpose of the Study:
- To review the epidemiology and evolution of emerging MRSA lineages, specifically ST105-SCCmecII.
- To synthesize current knowledge on the prevalence, genomic characteristics, and clinical impact of ST105-SCCmecII.
Main Methods:
- Comprehensive literature search of PubMed (inception to 2024) for studies on MRSA, CC5, ST5, and ST105.
- Inclusion of studies reporting ST105 MRSA occurrence in epidemiological studies.
- Selection of studies utilizing reliable genotyping methods (e.g., WGS, MLST) for lineage classification.
Main Results:
- ST105-SCCmecII is an emerging MRSA lineage prevalent in multiple countries, including Portugal, USA, and Brazil.
- It is identified as the second/third most significant CC5 lineage, frequently associated with bloodstream infections (BSI).
- Studies indicate increased mortality from BSI in patients over 15 years and higher prevalence in blood of patients over 60 years.
Conclusions:
- ST105-SCCmecII is a notable emerging MRSA clone with significant global presence.
- Its association with bloodstream infections and increased mortality in specific age groups warrants attention.
- Further research into the evolution and control of this lineage is crucial for public health.
