TY - JOUR

T1 - Whole genome sequencing reveals two genetically distinct MRSA outbreaks among people who inject drugs and homeless people in Copenhagen

AU - Bartels, Mette Damkjær

AU - Holm, Mona Katrine Alberthe

AU - Worning, Peder

AU - Stavad, Bodil

AU - Schneider, Uffe Vest

AU - Meiniche, Heidi

AU - Thiesen, Henrik

AU - Westh, Henrik

N1 - Publisher Copyright: © 2023 The Authors. APMIS published by John Wiley & Sons Ltd on behalf of Scandinavian Societies for Pathology, Medical Microbiology and Immunology.

PY - 2023

Y1 - 2023

N2 - Whole genome sequencing (WGS) has greatly improved the detection of methicillin-resistant Staphylococcus aureus (MRSA) transmission between people. We describe the transmission of two unique MRSA clones among homeless people in Copenhagen using WGS and core genome MLST (cgMLST). In 2014, an accumulation of MRSA bacteremia cases among homeless people admitted to our hospital was recognized, all having the rare MRSA spa t5147/ST88. The European Typology of Homelessness and Housing Exclusion (ETHOS) categories revealed that people who inject drugs (PWID) frequently visiting the milieu but living in private accommodation accounted for most cases. Hoping to terminate the transmission, 161 homeless people were MRSA screened in 2015, but no additional cases were found. From 2009 to 2018, 60 patients with genomically related t5147/ST88 isolates were found, of these 70% were confirmed to come from the homeless setting and 17% had bacteremia. From 2017 to 2020, cgMLST revealed a smaller MRSA outbreak including 13 PWID with a completely different clone, t1476/ST8, of which 15% had bacteremia. Our study confirms that WGS and cgMLST is excellent to reveal MRSA outbreaks. The ETHOS categorization can be useful to find the primary source of spread in the homeless community.

AB - Whole genome sequencing (WGS) has greatly improved the detection of methicillin-resistant Staphylococcus aureus (MRSA) transmission between people. We describe the transmission of two unique MRSA clones among homeless people in Copenhagen using WGS and core genome MLST (cgMLST). In 2014, an accumulation of MRSA bacteremia cases among homeless people admitted to our hospital was recognized, all having the rare MRSA spa t5147/ST88. The European Typology of Homelessness and Housing Exclusion (ETHOS) categories revealed that people who inject drugs (PWID) frequently visiting the milieu but living in private accommodation accounted for most cases. Hoping to terminate the transmission, 161 homeless people were MRSA screened in 2015, but no additional cases were found. From 2009 to 2018, 60 patients with genomically related t5147/ST88 isolates were found, of these 70% were confirmed to come from the homeless setting and 17% had bacteremia. From 2017 to 2020, cgMLST revealed a smaller MRSA outbreak including 13 PWID with a completely different clone, t1476/ST8, of which 15% had bacteremia. Our study confirms that WGS and cgMLST is excellent to reveal MRSA outbreaks. The ETHOS categorization can be useful to find the primary source of spread in the homeless community.

KW - cgMLST

KW - homeless

KW - MRSA

KW - PWID

KW - t1476/ST8

KW - t5147/ST88

KW - WGS

U2 - 10.1111/apm.13318

DO - 10.1111/apm.13318

M3 - Journal article

C2 - 37026991

AN - SCOPUS:85152965427

VL - 131

SP - 294

EP - 302

JO - A P M I S. Acta Pathologica, Microbiologica et Immunologica Scandinavica

JF - A P M I S. Acta Pathologica, Microbiologica et Immunologica Scandinavica

SN - 0903-4641

IS - 6

ER -