Whole-genome analysis uncovers loss of blaZ associated with carriage isolates belonging to methicillin-resistant Staphylococcus aureus (MRSA) clone ST5-VI in Cape Verde

• Published in: Journal of global antimicrobial resistance. Vol. 26; pp. 77 - 83
• Main Authors: Wysocka, Magdalena, Monteiro, Tamar, de Pina, Carine, Gonçalves, Deisy, de Pina, Sandrine, Ludgero-Correia, Antonio, Moreno, Joao, Zamudio, Roxana, Almebairik, Nada, Gray, Laura J., Pareek, Manish, Jenkins, David R., Aires-de-Sousa, Marta, De Lencastre, Herminia, Beleza, Sandra, Araujo, Isabel I., Conceição, Teresa, Oggioni, Marco R.
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.09.2021; Published by Elsevier Ltd. on behalf of International Society of Chemotherapy for Infection and Cancer; Elsevier
• Subjects: Antibiotic resistance; Cape Verde; Genomic epidemiology; Methicillin-resistant; MRSA; Staphylococcus aureus; Cape Verde; Genomic epidemiology; Methicillin-resistant; Staphylococcus aureus; Antibiotic resistance; MRSA
• ISSN: 2213-7165; 2213-7173
• DOI: 10.1016/j.jgar.2021.04.018

•One of the first whole genome analyses of Staphylococcus aureus carriage isolates in an African country.•Genome data allowed to place S. aureus isolates from Cape Verde in a phylogenetic context.•Loss of blaZ-carrying plasmids and transposons is not rare, which is also evident in other international MRSA isolates.•Steady increase in antimicrobial drug resistance in Cape Verde.•Data provide genomic information for the design of intervention measures to decrease antimicrobial resistance. Surveillance studies for Staphylococcus aureus carriage are a primary tool to survey the prevalence of methicillin-resistant S. aureus (MRSA) in the general population, patients and healthcare workers. We have previously reported S. aureus carriage in various African countries, including Cape Verde. Whole-genome sequences of 106 S. aureus isolates from Cape Verde were determined. Staphylococcus aureus carriage isolates in Cape Verde show high genetic variability, with the detection of 27 sequence types (STs) and three primary genetic clusters associated with ST152, ST15 and ST5. One transmission event with less than eight core-genome single nucleotide polymorphisms (cgSNP) differences was detected among the ST5-VI MRSA lineage. Genetic analysis confirmed the phenotypic resistance and allowed the identification of six independent events of plasmid or transposon loss associated with the deletion of blaZ in nine isolates. In the four ST5 MRSA isolates, loss of the blaZ plasmid coincided with the acquisition of SCCmec type VI and an unusual penicillin phenotype with a minimum inhibitory concentration (MIC) at the breakpoint, indicating an adaptation trend in this endemic lineage. Similar events of blaZ plasmid loss, with concomitant acquisition SCCmec elements, were detected among ST5 isolates from different geographical origins. Overall, the genome data allowed to place isolates in a phylogenetic context and to identify different blaZ gene deletions associated with plasmid or transposon loss. Genomic analysis unveiled adaptation and evolution trends, namely among emerging MRSA lineages in the country, which deserve additional consideration in the design of future infection control protocols.