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Volume 29, Number 5—May 2023
Research Letter

Panton-Valentine Leukocidin–Positive CC398 MRSA in Urban Clinical Settings, the Netherlands

Jairo GooskensComments to Author , Marja M. Konstantinovski, Margriet E.M. Kraakman, Jayant S. Kalpoe, Nathalie D. van Burgel, Eric C.J. Claas, and Thijs Bosch
Author affiliations: Leiden University Medical Center, Leiden, the Netherlands (J. Gooskens, M.M. Konstantinovski, M.E.M. Kraakman, E.C.J. Claas); Regional Public Health Laboratory Kennemerland, Haarlem, the Netherlands (J.S. Kalpoe); Haga Ziekenhuis, The Hague, the Netherlands (N.D. van Burgel); National Institute for Public Health and the Environment, Bilthoven, the Netherlands (T. Bosch)

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We report detection of Panton-Valentine leukocidin–positive clonal complex 398 human-origin methicillin-resistant Staphylococcus aureus L2 in the Netherlands. This hypervirulent lineage originated in the Asia-Pacific Region and could become community-acquired in Europe after recurrent travel-related introductions. Genomic surveillance enables early detection to guide control measures and help limit spread of pathogens in urban settings.

Staphylococcus aureus is a frequent cause of community- and healthcare-associated infections. Clonal complex 398 (CC398) is of particular concern because it includes common livestock-associated methicillin-resistant S. aureus (LA-MRSA) IIa subclades in Europe and human-origin MRSA (HO-MRSA) II-GOI subclades in the Asia-Pacific Region (14). Panton-Valentine leukocidin (PVL)–positive HO-MRSA L2 strains have recently emerged and are expanding geographically, causing skin and soft-tissue infections and occasional invasive disease in humans (2,3,5,6).

We report 3 patients in the Netherlands with infections caused by hypervirulent PVL-positive CC398 HO-MRSA L2 strains. The cases were detected as part of a CC398 MRSA surveillance study in a single urban area during 2014–2018 (7). One patient had furunculosis skin infection, 1 had a plantar abscess soft-tissue infection, and 1 patient with cystic fibrosis had recurrent bronchitis. One patient had a recent travel history to Vietnam in the Asia-Pacific Region, but none had livestock contact. Phenotypic susceptibility testing of patient samples confirmed methicillin resistance and the MRSA strains were sent to reference laboratories as part of routine molecular surveillance in the Netherlands. Whole-genome sequencing (WGS) and core genome multilocus sequence typing (cgMLST) were performed as part of the CC398 MRSA surveillance study. Detection of 3 PVL-positive CC398 isolates prompted comparative genomic analysis of single-nucleotide polymorphisms (SNPs) outside the scope of the surveillance study. The medical ethical committee of the Leiden University Medical Center approved the study protocol and waived the need for patient consent (approval no. G18.021/SH/sh).


Maximum-parsimony tree of Panton-Valentine leukocidin–positive CC398 MRSA detected in urban clinical settings, the Netherlands. Bold text indicates 3 HO-MRSA strains detected in this study, which we deposited in GenBank (accession nos. SRR21673410 for L2-P01, SRR21624599 for L2-P02, and SRR21673965 for L2-P03); those strains were compared with 27 CC398 Staphylococcus aureus strains from GenBank. The tree was constructed by using GenBank accession no. AM990992.1 as a reference strain, and then rooted and grouped into clades, as previously described (1). Scale bar indicates nucleotide substitutions per 100 sites based on a concatenated alignment of 3,878 high-quality single-nucleotide polymorphisms. HO-MRSA, human-origin MRSA; LA-MRSA, livestock-associated MRSA; MRSA, methicillin-resistant Staphylococcus aureus; MSSA, methicillin-susceptible S. aureus; ST, sequence type.

Figure. Maximum-parsimony tree of Panton-Valentine leukocidin–positive CC398 MRSA detected in urban clinical settings, the Netherlands. Bold text indicates 3 HO-MRSA strains detected in this study, which we deposited in GenBank (accession...

MLST showed sequence types (STs) belonging to CC398, including ST1232 (n = 2), a single-locus variant of ST398, and ST4081 (n = 1), a double-locus variant of ST398. WGS and comparative genomic analysis of SNPs confirmed that all isolates were part of the same L2 lineage within the II-GOI clade (Figure) (16). We performed cgMLST on 1,861 genes, and results showed each patient had a different complex type (CT), CT6700, CT6814, and CT7459, thus ruling out direct transmission events between the patients.

The L2 strains we detected carried resistance genes on the staphylococcal cassette chromosome mec element type V(5C2), including mecA, which confers β-lactam resistance, and pT181 plasmid integrated tetK, which confers tetracycline resistance. In addition, on other mobile genetic elements, the L2 strains carried erm(A), conferring macrolide-lincosamide-streptogramin resistance; ant(9)-Ia, conferring spectinomycin resistance; blaZ, conferring β-lactam resistance; and tet38, conferring tetracycline resistance. All 3 strains carried the same virulence markers, including the immune evasion cluster scn, chp, and sak; leukocidin pro-toxin subunits lukF-PV and lukS-PV; cna, ebp, ica, map, sdr, and srtB biofilm formation or microbial surface components recognizing adhesive matrix molecules; immune modulation markers adsA, cap8, and sbi; exoenzymes aur, geh, lip, and ssp; and exotoxins or effector delivery components hla, hld, hlg, esa, and esx (8). We deposited the 3 isolates in GenBank (accession nos. SRR21673410, SRR21624599, and SRR21673965) (Figure).

In conclusion, clinicians should be aware of recurrent introductions and evolutionary changes of hypervirulent PVL-positive CC398 HO-MRSA L2 strains in the Netherlands. All 3 patients carrying the detected strains manifested relevant infections, but clinical outcomes were not evaluated in the surveillance study. Additional studies could investigate travel-related transmission routes, disease burden, and clinical outcomes of patients. In addition, future studies could determine if PVL-positive CC398 HO-MRSA strains are becoming established as community-acquired pathogens in urban settings in Europe. We recommend active WGS surveillance for early clinical recognition of PVL-positive CC398 MRSA, which can guide prevention and control measures and limit interhuman transmission and severe clinical outcomes.

Dr. Gooskens is a clinical microbiologist at the Department of Medical Microbiology, Leiden University Medical Center, Leiden, the Netherlands. His current research interests focus on clinical molecular diagnostics and antimicrobial resistance of CC398 Staphylococcus aureus.

J.G. and M.E.M.K. conceptualized study and devised methods; J.G. prepared original manuscript draft; J.G., M.M.K., and M.E.M.K. interpreted data; J.G., M.M.K. reviewed and edited manuscript; J.G., J.S.K., N.D.v.B., E.C.J.C., and T.B. supervised study. All authors read and agreed to the final version of the manuscript.



This project was partially funded by the Antibiotic Resistance Network Holland West. The Dutch Ministry of Health, Welfare and Sport provided funding through Healthcare Project 21243 (Activity E).



  1. Price  LB, Stegger  M, Hasman  H, Aziz  M, Larsen  J, Andersen  PS, et al. Staphylococcus aureus CC398: host adaptation and emergence of methicillin resistance in livestock. MBio. 2012;3:e0030511. DOIPubMedGoogle Scholar
  2. Møller  JK, Larsen  AR, Østergaard  C, Møller  CH, Kristensen  MA, Larsen  J. International travel as source of a hospital outbreak with an unusual meticillin-resistant Staphylococcus aureus clonal complex 398, Denmark, 2016. Euro Surveill. 2019;24:1800680. DOIPubMedGoogle Scholar
  3. Coombs  GW, Daley  D, Shoby  P, Yee  NWT, Robinson  JO, Murray  R, et al. Genomic characterisation of CC398 MRSA causing severe disease in Australia. Int J Antimicrob Agents. 2022;59:106577. DOIPubMedGoogle Scholar
  4. Lu  H, Zhao  L, Si  Y, Jian  Y, Wang  Y, Li  T, et al. The surge of hypervirulent ST398 MRSA lineage with higher biofilm-forming ability is a critical threat to clinics. Front Microbiol. 2021;12:636788. DOIPubMedGoogle Scholar
  5. Williamson  DA, Bakker  S, Coombs  GW, Tan  H, Monecke  S, Heffernan  H. Emergence and molecular characterization of clonal complex 398 (CC398) methicillin-resistant Staphylococcus aureus (MRSA) in New Zealand. J Antimicrob Chemother. 2014;69:142830. DOIPubMedGoogle Scholar
  6. Kaneko  H, Kim  ES, Yokomori  S, Moon  SM, Song  KH, Jung  J, et al. Comparative genomic analysis of the human variant of methicillin-resistant Staphylococcus aureus CC398 in Japan and Korea. Microb Drug Resist. 2022;28:3307. DOIPubMedGoogle Scholar
  7. Konstantinovski  MM, Schouls  LM, Witteveen  S, Claas  ECJ, Kraakman  ME, Kalpoe  J, et al. Livestock-associated methicillin-resistant Staphylococcus aureus epidemiology, genetic diversity, and clinical characteristics in an urban region. Front Microbiol. 2022;13:875775. DOIPubMedGoogle Scholar
  8. Strauß  L, Ruffing  U, Abdulla  S, Alabi  A, Akulenko  R, Garrine  M, et al. Detecting Staphylococcus aureus virulence and resistance genes: a comparison of whole-genome sequencing and DNA microarray technology. J Clin Microbiol. 2016;54:100816. DOIPubMedGoogle Scholar




Cite This Article

DOI: 10.3201/eid2905.221717

Original Publication Date: March 13, 2023

Table of Contents – Volume 29, Number 5—May 2023

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Jairo Gooskens, Department of Medical Microbiology, Leiden University Medical Center, Albinusdreef 2, Leiden 2333, the Netherlands

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Page created: February 23, 2023
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