title: New patterns of methicillin-resistant Staphylococcus aureus (MRSA) clones, community-associated MRSA genotypes behave like healthcare-associated MRSA genotypes within hospitals, Argentina.
abstract: Methicillin-resistant Staphylococcus aureus (MRSA) burden is increasing worldwide in hospitals [healthcare-associated (HA)-MRSA] and in communities [community-associated (CA)-MRSA]. However, the impact of CA-MRSA within hospitals remains limited, particularly in Latin America. A countrywide representative survey of S. aureus infections was performed in Argentina by analyzing 591 clinical isolates from 66 hospitals in a prospective cross-sectional, multicenter study (Nov-2009). This work involved healthcare-onset infections-(HAHO, >48 hospitalization hours) and community-onset (CO) infections [including both, infections (HACO) in patients with healthcare-associated risk-factors (HRFs) and infections (CACO) in those without HRFs]. MRSA strains were genetically typed as CA-MRSA and HA-MRSA genotypes (CA-MRSAG and HA-MRSAG) by SCCmec- and spa-typing, PFGE, MLST and virulence genes profile by PCR. Considering all isolates, 63% were from CO-infections and 55% were MRSA [39% CA-MRSAG and 16% HA-MRSAG]. A significantly higher MRSA proportion among CO- than HAHO-S. aureus infections was detected (58% vs 49%); mainly in children (62% vs 43%). The CA-MRSAG/HA-MRSAG have accounted for 16%/33% of HAHO-, 39%/13% of HACO- and 60.5%/0% of CACO-infections. Regarding the epidemiological associations identified in multivariate models for patients with healthcare-onset CA-MRSAG infections, CA-MRSAG behave like HA-MRSAG within hospitals but children were the highest risk group for healthcare-onset CA-MRSAG infections. Most CA-MRSAG belonged to two major clones: PFGE-type N-ST30-SCCmecIVc-t019-PVL(+) and PFGE-type I-ST5-IV-SCCmecIVa-t311-PVL(+) (45% each). The ST5-IV-PVL(+)/ST30-IV-PVL(+) clones have caused 31%/33% of all infections, 20%/4% of HAHO-, 43%/23% of HACO- and 35%/60% of CACO- infections, with significant differences by age groups (children/adults) and geographical regions. Importantly, an isolate belonging to USA300-0114-(ST8-SCCmecIVa-spat008-PVL(+)-ACME(+)) was detected for the first time in Argentina. Most of HA-MRSAG (66%) were related to the Cordobes/Chilean clone-(PFGE-type A-ST5-SCCmecI-t149) causing 18% of all infections (47% of HAHO- and 13% of HACO-infections). Results strongly suggest that the CA-MRSA clone ST5-IV-PVL(+) has begun to spread within hospitals, replacing the traditional Cordobes/Chilean-HA-MRSA clone ST5-I-PVL(-), mainly in children. Importantly, a growing MRSA reservoir in the community was associated with spreading of two CA-MRSA clones: ST5-IV-PVL(+), mainly in children with HRFs, and ST30-IV-PVL(+) in adults without HRFs. This is the first nationwide study in Argentina providing information about the molecular and clinical epidemiology of CA-MRSA, particularly within hospitals, which is essential for designing effective control measures in this country and worldwide.
authors.affiliation: Centro de Investigaciones en Bioquímica Clínica e Inmunología (CIBICI) CONICET and Departamento de Bioquímica Clínica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Córdoba, Argentina.
authors.forename: Ana L
authors.initials: AL
authors.lastname: Egea
authors.affiliation: Servicio Antimicrobianos, Instituto Nacional de Enfermedades Infecciosas (INEI)-ANLIS "Dr. Carlos G. Malbrán", Ciudad Autónoma de Buenos Aires, Argentina.
authors.forename: Paula
authors.initials: P
authors.lastname: Gagetti
authors.affiliation: Cátedra de Infectología I, Hospital Rawson, Facultad de Ciencias Médicas, Universidad Nacional de Córdoba, Córdoba, Argentina.
authors.forename: Ricardo
authors.initials: R
authors.lastname: Lamberghini
authors.affiliation: Servicio Antimicrobianos, Instituto Nacional de Enfermedades Infecciosas (INEI)-ANLIS "Dr. Carlos G. Malbrán", Ciudad Autónoma de Buenos Aires, Argentina.
authors.forename: Diego
authors.initials: D
authors.lastname: Faccone
authors.affiliation: Servicio Antimicrobianos, Instituto Nacional de Enfermedades Infecciosas (INEI)-ANLIS "Dr. Carlos G. Malbrán", Ciudad Autónoma de Buenos Aires, Argentina.
authors.forename: Celeste
authors.initials: C
authors.lastname: Lucero
authors.affiliation: Laboratorio de Infecciones Nosocomiales, Instituto de Salud Carlos III, Centro Nacional de Microbiología, Majadahonda, Madrid, Spain.
authors.forename: Ana
authors.initials: A
authors.lastname: Vindel
authors.affiliation: Area de Informática Médica, Facultad de Medicina, Universidad Católica de Córdoba, Córdoba, Argentina.
authors.forename: Dario
authors.initials: D
authors.lastname: Tosoroni
authors.affiliation: Servicio de Infectología, Hospital de Niños de la Santísima Trinidad, Córdoba, Argentina.
authors.forename: Analía
authors.initials: A
authors.lastname: Garnero
authors.affiliation: Centro de Investigaciones en Bioquímica Clínica e Inmunología (CIBICI) CONICET and Departamento de Bioquímica Clínica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Córdoba, Argentina.
authors.forename: Hector A
authors.initials: HA
authors.lastname: Saka
authors.affiliation: Servicio Antimicrobianos, Instituto Nacional de Enfermedades Infecciosas (INEI)-ANLIS "Dr. Carlos G. Malbrán", Ciudad Autónoma de Buenos Aires, Argentina.
authors.forename: Marcelo
authors.initials: M
authors.lastname: Galas
authors.affiliation: Centro de Investigaciones en Bioquímica Clínica e Inmunología (CIBICI) CONICET and Departamento de Bioquímica Clínica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Córdoba, Argentina.
authors.forename: José L
authors.initials: JL
authors.lastname: Bocco
authors.affiliation: Servicio Antimicrobianos, Instituto Nacional de Enfermedades Infecciosas (INEI)-ANLIS "Dr. Carlos G. Malbrán", Ciudad Autónoma de Buenos Aires, Argentina. Electronic address: acorso@anlis.gov.ar.
authors.forename: Alejandra
authors.initials: A
authors.lastname: Corso
authors.affiliation: Centro de Investigaciones en Bioquímica Clínica e Inmunología (CIBICI) CONICET and Departamento de Bioquímica Clínica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Córdoba, Argentina. Electronic address: csola@fcq.unc.edu.ar.
authors.forename: Claudia
authors.initials: C
authors.lastname: Sola
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001118:Argentina; D002648:Child; D002675:Child, Preschool; D016000:Cluster Analysis; D017714:Community-Acquired Infections / Q000382:microbiology*; D003428:Cross Infection / Q000382:microbiology*; D003430:Cross-Sectional Studies; D005260:Female; D005838:Genotype; D006761:Hospitals; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D055624:Methicillin-Resistant Staphylococcus aureus / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification*; D008875:Middle Aged; D058889:Molecular Typing; D011446:Prospective Studies; D013203:Staphylococcal Infections / Q000382:microbiology*; D037521:Virulence Factors / Q000235:genetics; D055815:Young Adult
chemical_list: D037521:Virulence Factors
keywords: Argentina; Community-onset infections; Healtcare-onset infections; MRSA; ST30; ST5