Clonal Diversity and Genetic Landscape of mecC-Positive S. aureus in Human Samples from Iran: First Report of CC/ST423/t742

Goudarzi, Mehdi; Seyedjavadi, Sima Sadat; Raigani, Mozhgan; Salehi, Zahra; Dadashi, Masoud; Nasiri, Mohammad Javad

doi:10.61882/ibj.5161

Volume 30, Issue 3 And 2 (4-2026) IBJ 2026, 30(3 And 2): 174-187 | Back to browse issues page

‎ 10.61882/ibj.5161

PMID: 42472314

Mendeley

Zotero

RefWorks

Goudarzi M, Seyedjavadi S S, Raigani M, Salehi Z, Dadashi M, Nasiri M J. Clonal Diversity and Genetic Landscape of mecC-Positive S. aureus in Human Samples from Iran: First Report of CC/ST423/t742. IBJ 2026; 30 (3 and 2) :174-187
URL: http://ibj.pasteur.ac.ir/article-1-5161-en.html

Clonal Diversity and Genetic Landscape of mecC-Positive S. aureus in Human Samples from Iran: First Report of CC/ST423/t742

Mehdi Goudarzi ^*

, Sima Sadat Seyedjavadi

, Mozhgan Raigani

, Zahra Salehi

, Masoud Dadashi

, Mohammad Javad Nasiri

Abstract:

Background: The emergence of mecC-carrying Staphylococcus aureus strains is a serious concern in public health. Our study investigated the clonal diversity, genetic characteristics, antimicrobial resistance, virulence determinants, biofilm-forming ability, and molecular epidemiology of mecC-positive Staphylococcus aureus isolates obtained from hospitalized patients in Iran.
Methods: We analyzed 45 mecC-carrying S. aureus strains isolated from 1,590 S. aureus samples collected from different clinical sources. The characterization included antimicrobial susceptibility tests, assessment of biofilm formation, spa typing, multilocus sequence typing (MLST), and PCR analysis to detect resistance, biofilm-related, and virulence genes.
Results: Our results showed that 17.8%, 17.8%, and 64.4% of the isolates were classified as weak, intermediate, and strong biofilm producers, respectively. The prevalence of the ant(4΄)-Ia and tet(M) was found in 80% and 73.3% of the isolates, respectively. MLST revealed that the 45 isolates belonged to four clonal complexes: CC8 (44.4%), CC130 (24.5%), CC121 (17.8%), and CC425 (13.3%). The majority of S. aureus isolates belonged to the CC8/ST239 lineage (44.4%). Also, tst-positive strains belonged to CC121/ST599/t5930 (17.8%) and CC8/ST239/t037 (11.1%), while eta-positive isolates belonged to CC/ST130/t843 (15.6%). Fusidic acid-resistant S. aureus isolates primarily belonged to CC8/ST239/t037 lineage (11.1%), followed by CC8/ST239/t7688 (6.7%), both carrying the fusB gene. Vancomycin-intermediate S. aureus strains were classified into CC/ST599/t5930 (6.7%) and CC/ST130/t843 (4.4%) clones.
Conclusion: This study highlights the need for close and continuous monitoring of the genetic diversity and characteristics of the mecC-carrying S. aureus strains. Besides, urgent measures are required to prevent the transmission of these strains and to effectively treat associated infections.

Keywords: Hospitals, Methicillin-resistant Staphylococcus aureus, Staphylococcus aureus

Full-Text [PDF 1436 kb]

Type of Study: Full Length/Original Article | Subject: Molecular Microbiology

References

1. Tong SYC, Davis JS, Eichenberger E, Holland TL, Fowler Jr VG. Staphylococcus aureus infections: Epidemiology, pathophysiology, clinical manifestations, and management. Clin Microbiol Rev. 2015;28(3):603-61. [DOI:10.1128/CMR.00134-14]

2. Lee AS, De Lencastre H, Garau J, Kluytmans J, Malhotra-Kumar S, Peschel A, et al. Methicillin- resistant Staphylococcus aureus. Nat Rev Dis Primers. 2018:4:18033. [DOI:10.1038/nrdp.2018.33]

3. Paterson GK, Harrison EM, Holmes MA. The emergence of mecC methicillin-resistant Staphylococcus aureus. Trends Microbiol. 2014;22(1):42-7. [DOI:10.1016/j.tim.2013.11.003]

4. Petersen A, Stegger M, Heltberg O, Christensen J, Zeuthen A, Knudsen LK, et al. Epidemiology of methicillin-resistant Staphylococcus aureus carrying the novel mecC gene in Denmark corroborates a zoonotic reservoir with transmission to humans. Clin Microbiol Infect. 2013;19(1):16-22. [DOI:10.1111/1469-0691.12036]

5. Lozano C, Fernández-Fernández R, Ruiz-Ripa L, Gómez P, Zarazaga M, Torres C. Human mecC- carrying MRSA: Clinical implications and risk factors. Microorganisms. 2020;8(10):1615. [DOI:10.3390/microorganisms8101615]

6. Paterson GK, Morgan FJE, Harrison EM, Cartwright EJP, Török ME, Zadoks RN, et al. Prevalence and characterization of human mecC methicillin-resistant Staphylococcus aureus isolates in England. J Antimicrob Chemother. 2014;69(4):907-10. [DOI:10.1093/jac/dkt462]

7. Porrero MC, Valverde A, Fernández-Llario P, Díez-Guerrier A, Mateos A, Lavin S, et al. Staphylococcus aureus carrying mecC gene in animals and urban wastewater, Spain. Emerg Infect Dis. 2014;20(5):899-901. [DOI:10.3201/eid2005.130426]

8. García-Álvarez L, Holden MTG, Lindsay H, Webb CR, Brown DFJ, Curran MD, et al. Meticillin-resistant Staphylococcus aureus with a novel mecA homologue in human and bovine populations in the UK and Denmark: A descriptive study. Lancet Infect Dis. 2011;11(8):595-603. [DOI:10.1016/S1473-3099(11)70126-8]

9. Goudarzi M, Navidinia M, Dadashi M, Hashemi A, Pouriran R. First report of methicillin-resistant Staphylococcus aureus carrying the mecC gene in human samples from Iran: Prevalence and molecular characteristics. New Microbes New Infect. 2021:39:100832. [DOI:10.1016/j.nmni.2020.100832]

10. Goudarzi M, Kobayashi N, Dadashi M, Pantůček R, Nasiri MJ, Fazeli M, et al. Prevalence, genetic diversity, and temporary shifts of inducible clindamycin resistance Staphylococcus aureus clones in Tehran, Iran: A molecular-epidemiological analysis from 2013 to 2018. Front Microbiol. 2020:11:663. [DOI:10.3389/fmicb.2020.00663]

11. Goudarzi M, Tayebi Z, Dadashi M, Miri M, Amirpour A, Fazeli M. Characteristics of community- acquired methicillin-resistant Staphylococcus aureus associated with wound infections in Tehran, Iran: High prevalence of PVL+ t008 and the emergence of new spa types t657, t5348, and t437 in Iran. Gene Rep. 2020:19:100603. [DOI:10.1016/j.genrep.2020.100603]

12. Harmsen D, Claus H, Witte W, Rothganger J, Claus H, Turnwald D, et al. Typing of methicillin- resistant Staphylococcus aureus in a university hospital setting by using novel software for spa repeat determination and database management. J Clin Microbiol. 2003;41(12):5442-8. [DOI:10.1128/JCM.41.12.5442-5448.2003]

13. Enright MC, Day NP, Davies CE, Peacock SJ, Spratt BG. Multilocus sequence typing for characterization of methicillin-resistant and methicillin-susceptible clones of Staphylococcus aureus. J Clin Microbiol. 2000;38(3):1008-15. [DOI:10.1128/JCM.38.3.1008-1015.2000]

14. Diaz R, Ramalheira E, Afreixo V, Gago B. Methicillin-resistant Staphylococcus aureus carrying the new mecC gene-a meta-analysis. Diagn Microbiol Infect Dis. 2015;84(2):135-40. [DOI:10.1016/j.diagmicrobio.2015.10.014]

15. Moghaddam PZ, Azimian A, Sepahy AA, Iranbakhsh A. Isolation and genetic characterization of vancomycin-resistant and mecC+ methicillin-resistant Staphylococcus aureus strains in clinical samples of Bojnurd, Northeastern Iran. Jundishapur J Microbiol. 2021;14(10):118949. [DOI:10.5812/jjm.118949]

16. Idrees MM, Saeed K, Shahid MA, Akhtar M, Qammar K, Hassan J, et al. Prevalence of mecA-and mecC-associated methicillin-resistant Staphylococcus aureus in clinical specimens, Punjab, Pakistan. Biomedicines. 2023;11(3):878. [DOI:10.3390/biomedicines11030878]

17. Kim C, Milheiriço C, Gardete S, Holmes MA, Holden MT, De Lencastre H, et al. Properties of a novel PBP2A protein homolog from Staphylococcus aureus strain LGA251 and its contribution to the β-lactam-resistant phenotype. J Biol Chem. 2012;287(44):36854-63. [DOI:10.1074/jbc.M112.395962]

18. Ghasemzadeh-Moghaddam H, Azimian A, Bayani G, Dashti V, Nojoomi S, Shirazi N, et al. High prevalence and expression of antiseptic resistance genes among infectious t037/ST239 methicillin-resistant Staphylococcus aureus (MRSA) strains in North Khorasan Province, Iran. Iran J Basic Med Sci.2022;25(6):775-80.

19. Larsen J, Raisen CL, Ba X, Sadgrove NJ, Padilla-González GF, Simmonds MS, et al. Emergence of methicillin resistance predates the clinical use of antibiotics. Nature. 2022;602(7895):135-41. [DOI:10.1038/s41586-021-04265-w]

20. Kerschner H, Harrison EM, Hartl R, Holmes MA, Apfalter P. First report of mecC MRSA in human samples from Austria: Molecular characteristics and clinical data. New Microbes New Infect. 2014:3:4-9. [DOI:10.1016/j.nmni.2014.11.001]

21. Lindgren A-K, Gustafsson E, Petersson AC, Melander E. Methicillin-resistant Staphylococcus aureus with mecC: A description of 45 human cases in southern Sweden. Eur J Clin Microbiol Infect Dis. 2016;35(6):971-5. [DOI:10.1007/s10096-016-2624-x]

22. Shariati A, Dadashi M, Moghadam MT, Van Belkum A, Yaslianifard S, Darban-Sarokhalil D. Global prevalence and distribution of vancomycin-resistant, vancomycin intermediate and heterogeneously vancomycin intermediate Staphylococcus aureus clinical isolates: A systematic review and meta-analysis. Sci Rep. 2020;10(1):12689. [DOI:10.1038/s41598-020-69058-z]

23. Udo EE, Al-Sweih N, Mokaddas E, Johny M, Dhar R, Gomaa HH, et al. Antibacterial resistance and their genetic location in MRSA isolated in Kuwait hospitals, 1994-2004. BMC Infect Dis. 2006:6:168. [DOI:10.1186/1471-2334-6-168]

24. Zamani S, Mohammadi A, Hajikhani B, Abiri P, Fazeli M, Nasiri MJ, et al. Mupirocin-Resistant Staphylococcus aureus in Iran: A biofilm production and genetic characteristics. Biomed Res Int. 2022:2022:7408029. [DOI:10.1155/2022/7408029]

25. Hajikhani B, Goudarzi M, Kakavandi S, Amini S, Zamani S, Van Belkum A, et al. The global prevalence of fusidic acid resistance in clinical isolates of Staphylococcus aureus: A systematic review and meta- analysis. Antimicrob Resist Infect Control. 2021;10(1):75. [DOI:10.1186/s13756-021-00943-6]

26. Bali N, Borkakoty B, Bashir H, Nazir S, Wani S, Mir A, et al. Isolation of the mecC gene carrying methicillin-resistant Staphylococcus aureus in clinical samples from a tertiary care institute, Northern India. J Clin Diagn Res. 2021;15(10):11-15. [DOI:10.7860/JCDR/2021/50312.15525]

27. Khan AA, Ali A, Tharmalingam N, Mylonakis E, Zahra R. First report of mecC gene in clinical methicillin-resistant S. aureus (MRSA) from tertiary care hospital Islamabad, Pakistan. J Infect Public Health. 2020;13(10):1501-7. [DOI:10.1016/j.jiph.2020.05.017]

28. Chen C-J, Huang Y-C. New epidemiology of Staphylococcus aureus infection in Asia. Clin Microbiol Infect. 2014;20(7):605-23. [DOI:10.1111/1469-0691.12705]

29. Mirzaii M, Emaneini M, Jabalameli F, Halimi S, Taherikalani M. Molecular investigation of Staphylococcus aureus isolated from the patients, personnel, air and environment of an ICU in a hospital in Tehran. J Infect Public Health. 2015;8(2):202-6. [DOI:10.1016/j.jiph.2014.09.002]

30. Monecke S, Coombs G, Shore AC, Coleman DC, Akpaka P, Borg M, et al. A field guide to pandemic, epidemic and sporadic clones of methicillin-resistant Staphylococcus aureus. Plos One. 2011;6(4):17936. [DOI:10.1371/journal.pone.0017936]

31. Boswihi SS, Udo EE, Al-Sweih N. Shifts in the clonal distribution of methicillin-resistant Staphylococcus aureus in Kuwait hospitals: 1992-2010. Plos One. 2016;11(9):0162744. [DOI:10.1371/journal.pone.0162744]

32. Yu F, Liu Y, Lu C, Lv J, Qi X, Ding Y, et al. Dissemination of fusidic acid resistance among Staphylococcus aureus clinical isolates. BMC Microbiol. 2015:15:210. [DOI:10.1186/s12866-015-0552-z]

33. Chen HJ, Hung WC, Tseng SP, Tsai JC, Hsueh PR, Teng L-J. Fusidic acid resistance determinants in Staphylococcus aureus clinical isolates. Antimicrob Agents Chemother. 2010;54(12):4985-91. [DOI:10.1128/AAC.00523-10]

34. García-Garrote F, Cercenado E, Marín M, Bal M, Trincado P, Corredoira J, et al. Methicillin-resistant Staphylococcus aureus carrying the mecC gene: Emergence in Spain and report of a fatal case of bacteraemia. J Antimicrob Chemother. 2014;69(1):45-50. [DOI:10.1093/jac/dkt327]

35. Dermota U, Zdovc I, Strumbelj I, Grmek-Kosnik I, Ribic H, Rupnik M, et al. Detection of methicillin-resistant Staphylococcus aureus carrying the mecC gene in human samples in Slovenia. Epidemiol Infect. 2015;143(5):1105-8. [DOI:10.1017/S0950268814001861]

36. Sabat AJ, Koksal M, Akkerboom V, Monecke S, Kriegeskorte A, Hendrix R, et al. Detection of new methicillin-resistant Staphylococcus aureus strains that carry a novel genetic homologue and important virulence determinants. J Clin Microbiol. 2012;50(10):3374-7. [DOI:10.1128/JCM.01121-12]

37. Silva V, Ferreira E, Manageiro V, Reis L, Tejedor-Junco MT, Sampaio A, et al. Distribution and clonal diversity of Staphylococcus aureus and other staphylococci in surface waters: Detection of ST425-t742 and ST130-t843 mecC-positive MRSA strains. Antibiotics. 2021;10(11):1416. [DOI:10.3390/antibiotics10111416]

Rights and permissions
	This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.

Designed & Developed by : Yektaweb

Iranian

Biomedical Journal